core/sched: clean up
core/sched: clean up

- remove stray spaces
- remove TODOs:
    - MODULE_HWTIMER is not a module anymore
    - checking for NULL is necessary, at least without API changes:
      `sched_task_exit` sets `sched_active_thread` to `NULL`, then exits,
      afterwards `cpu_switch_context_exit` calls `sched_run`

koenning/RIOT,shady33/RIOT,msolters/RIOT,nsol-nmsu/RIOT,A-Paul/RIOT,foss-for-synopsys-dwc-arc-processors/RIOT,immesys/RiSyn,gbarnett/RIOT,dailab/RIOT,Josar/RIOT,Lexandro92/RIOT-CoAP,herrfz/RIOT-old,binarylemon/RIOT,watr-li/RIOT,rfuentess/RIOT,openkosmosorg/RIOT,daniel-k/RIOT,wentaoshang/RIOT,cladmi/RIOT,attdona/RIOT,tdautc19841202/RIOT,rfswarm/RIOT,neumodisch/RIOT,katezilla/RIOT,jfischer-phytec-iot/RIOT,ant9000/RIOT,A-Paul/RIOT,rfswarm/RIOT,stevenj/RIOT,immesys/RiSyn,authmillenon/RIOT,ThanhVic/RIOT,rfswarm2/RIOT,benoit-canet/RIOT,rfswarm2/RIOT,avmelnikoff/RIOT,rfswarm/RIOT,neiljay/RIOT,ximus/RIOT,abp719/RIOT,mfrey/RIOT,dhruvvyas90/RIOT,basilfx/RIOT,josephnoir/RIOT,alignan/RIOT,dailab/RIOT,BytesGalore/RIOT,patkan/RIOT,dhruvvyas90/RIOT,ximus/RIOT,khhhh/RIOT,ntrtrung/RIOT,kb2ma/RIOT,wentaoshang/RIOT,sumanpanchal/RIOT,roberthartung/RIOT,thomaseichinger/RIOT,syin2/RIOT,l3nko/RIOT,abp719/RIOT,kushalsingh007/RIOT,benoit-canet/RIOT,RubikonAlpha/RIOT,patkan/RIOT,thiagohd/RIOT,BytesGalore/PetersRIOT,ThanhVic/RIOT,khhhh/RIOT,LudwigOrtmann/RIOT,OlegHahm/RIOT,lazytech-org/RIOT,msolters/RIOT,miri64/RIOT,dkm/RIOT,ros2/ros2_embedded_riot,shady33/RIOT,biboc/RIOT,OTAkeys/RIOT,asanka-code/RIOT,lazytech-org/RIOT,immesys/RiSyn,JensErdmann/RIOT,msolters/RIOT,kaleb-himes/RIOT,mtausig/RIOT,OTAkeys/RIOT,jhollister/RIOT,ant9000/RIOT,Josar/RIOT,zhuoshuguo/RIOT,biboc/RIOT,wentaoshang/RIOT,PSHIVANI/Riot-Code,A-Paul/RIOT,robixnai/RIOT,yogo1212/RIOT,OlegHahm/RIOT,ant9000/RIOT,authmillenon/RIOT,jbeyerstedt/RIOT-OTA-update,neiljay/RIOT,ximus/RIOT,MarkXYang/RIOT,fnack/RIOT,herrfz/RIOT,beurdouche/RIOT,shady33/RIOT,toonst/RIOT,ros2/ros2_embedded_riot,rousselk/RIOT,luciotorre/RIOT,Yonezawa-T2/RIOT,smlng/RIOT,RBartz/RIOT,BytesGalore/PetersRIOT,yogo1212/RIOT,benoit-canet/RIOT,katezilla/RIOT,avmelnikoff/RIOT,koenning/RIOT,herrfz/RIOT,ThanhVic/RIOT,kushalsingh007/RIOT,stevenj/RIOT,alignan/RIOT,jasonatran/RIOT,neumodisch/RIOT,arvindpdmn/RIOT,katezilla/RIOT,arvindpdmn/RIOT,abp719/RIOT,kYc0o/RIOT,BytesGalore/RIOT,Darredevil/RIOT,mtausig/RIOT,daniel-k/RIOT,MarkXYang/RIOT,Osblouf/RIOT,katezilla/RIOT,emmanuelsearch/RIOT,kerneltask/RIOT,roberthartung/RIOT,openkosmosorg/RIOT,thiagohd/RIOT,jferreir/RIOT,rousselk/RIOT,Josar/RIOT,foss-for-synopsys-dwc-arc-processors/RIOT,brettswann/RIOT,alex1818/RIOT,ks156/RIOT,rfswarm/RIOT,EmuxEvans/RIOT,patkan/RIOT,1blankz7/RIOT,chris-wood/RIOT,locicontrols/RIOT,watr-li/RIOT,l3nko/RIOT,sumanpanchal/RIOT,BytesGalore/PetersRIOT,JensErdmann/RIOT,Ell-i/RIOT,Hyungsin/RIOT-OS,rfswarm/RIOT,arvindpdmn/RIOT,patkan/RIOT,abp719/RIOT,rakendrathapa/RIOT,stevenj/RIOT,smlng/RIOT,ximus/RIOT,bartfaizoltan/RIOT,RBartz/RIOT,adrianghc/RIOT,haoyangyu/RIOT,tfar/RIOT,rajma996/RIOT,JensErdmann/RIOT,Ell-i/RIOT,centurysys/RIOT,l3nko/RIOT,benoit-canet/RIOT,ntrtrung/RIOT,Lexandro92/RIOT-CoAP,patkan/RIOT,abkam07/RIOT,fnack/RIOT,MohmadAyman/RIOT,luciotorre/RIOT,PSHIVANI/Riot-Code,thiagohd/RIOT,immesys/RiSyn,Lexandro92/RIOT-CoAP,EmuxEvans/RIOT,neiljay/RIOT,benoit-canet/RIOT,JensErdmann/RIOT,daniel-k/RIOT,sgso/RIOT,RBartz/RIOT,abkam07/RIOT,d00616/RIOT,A-Paul/RIOT,daniel-k/RIOT,dkm/RIOT,binarylemon/RIOT,automote/RIOT,chris-wood/RIOT,alignan/RIOT,emmanuelsearch/RIOT,A-Paul/RIOT,phiros/RIOT,centurysys/RIOT,rousselk/RIOT,cladmi/RIOT,kushalsingh007/RIOT,herrfz/RIOT-old,luciotorre/RIOT,RBartz/RIOT,nsol-nmsu/RIOT,aeneby/RIOT,bartfaizoltan/RIOT,kYc0o/RIOT,LudwigKnuepfer/RIOT,bartfaizoltan/RIOT,malosek/RIOT,rfswarm/RIOT,altairpearl/RIOT,MohmadAyman/RIOT,PSHIVANI/Riot-Code,khhhh/RIOT,haoyangyu/RIOT,changbiao/RIOT,AnonMall/RIOT,centurysys/RIOT,gautric/RIOT,d00616/RIOT,gautric/RIOT,gebart/RIOT,tfar/RIOT,DipSwitch/RIOT,alex1818/RIOT,attdona/RIOT,LudwigKnuepfer/RIOT,kbumsik/RIOT,dailab/RIOT,kaleb-himes/RIOT,ks156/RIOT,rfuentess/RIOT,abkam07/RIOT,kaleb-himes/RIOT,FrancescoErmini/RIOT,yogo1212/RIOT,cladmi/RIOT,syin2/RIOT,LudwigKnuepfer/RIOT,wentaoshang/RIOT,sumanpanchal/RIOT,herrfz/RIOT-old,kb2ma/RIOT,Lotterleben/RIOT,l3nko/RIOT,kerneltask/RIOT,koenning/RIOT,luciotorre/RIOT,Lotterleben/RIOT,MonsterCode8000/RIOT,abkam07/RIOT,x3ro/RIOT,jremmert-phytec-iot/RIOT,d00616/RIOT,kbumsik/RIOT,adjih/RIOT,MonsterCode8000/RIOT,PSHIVANI/Riot-Code,rajma996/RIOT,hamilton-mote/RIOT-OS,sgso/RIOT,kushalsingh007/RIOT,locicontrols/RIOT,sumanpanchal/RIOT,chris-wood/RIOT,LudwigOrtmann/RIOT,jhollister/RIOT,x3ro/RIOT,smlng/RIOT,avmelnikoff/RIOT,ros2/ros2_embedded_riot,watr-li/RIOT,ros2/ros2_embedded_riot,Lexandro92/RIOT-CoAP,attdona/RIOT,Osblouf/RIOT,smlng/RIOT,toonst/RIOT,kerneltask/RIOT,binarylemon/RIOT,changbiao/RIOT,brettswann/RIOT,toonst/RIOT,mziegert/RIOT,attdona/RIOT,kerneltask/RIOT,rajma996/RIOT,ntrtrung/RIOT,gautric/RIOT,centurysys/RIOT,DipSwitch/RIOT,neumodisch/RIOT,adrianghc/RIOT,Hyungsin/RIOT-OS,cladmi/RIOT,Ell-i/RIOT,rajma996/RIOT,emmanuelsearch/RIOT,avmelnikoff/RIOT,jferreir/RIOT,biboc/RIOT,BytesGalore/RIOT,RBartz/RIOT,ntrtrung/RIOT,ks156/RIOT,alex1818/RIOT,jhollister/RIOT,MohmadAyman/RIOT,centurysys/RIOT,sumanpanchal/RIOT,ntrtrung/RIOT,aeneby/RIOT,jfischer-phytec-iot/RIOT,lebrush/RIOT,alex1818/RIOT,BytesGalore/PetersRIOT,kbumsik/RIOT,abp719/RIOT,jhollister/RIOT,foss-for-synopsys-dwc-arc-processors/RIOT,RubikonAlpha/RIOT,daniel-k/RIOT,gebart/RIOT,1blankz7/RIOT,altairpearl/RIOT,hamilton-mote/RIOT-OS,OTAkeys/RIOT,Lexandro92/RIOT-CoAP,adrianghc/RIOT,attdona/RIOT,roberthartung/RIOT,rakendrathapa/RIOT,mtausig/RIOT,rfswarm2/RIOT,fnack/RIOT,cladmi/RIOT,EmuxEvans/RIOT,ks156/RIOT,wentaoshang/RIOT,ThanhVic/RIOT,rousselk/RIOT,LudwigKnuepfer/RIOT,altairpearl/RIOT,gebart/RIOT,MarkXYang/RIOT,Ell-i/RIOT,OTAkeys/RIOT,alex1818/RIOT,Darredevil/RIOT,sgso/RIOT,alignan/RIOT,brettswann/RIOT,phiros/RIOT,emmanuelsearch/RIOT,latsku/RIOT,RIOT-OS/RIOT,miri64/RIOT,roberthartung/RIOT,miri64/RIOT,phiros/RIOT,rfuentess/RIOT,jbeyerstedt/RIOT-OTA-update,Yonezawa-T2/RIOT,marcosalm/RIOT,foss-for-synopsys-dwc-arc-processors/RIOT,sgso/RIOT,brettswann/RIOT,Yonezawa-T2/RIOT,jremmert-phytec-iot/RIOT,jbeyerstedt/RIOT-OTA-update,thomaseichinger/RIOT,kaspar030/RIOT,gebart/RIOT,khhhh/RIOT,ximus/RIOT,nsol-nmsu/RIOT,plushvoxel/RIOT,kaspar030/RIOT,DipSwitch/RIOT,khhhh/RIOT,herrfz/RIOT-old,rfuentess/RIOT,altairpearl/RIOT,jferreir/RIOT,RIOT-OS/RIOT,lebrush/RIOT,authmillenon/RIOT,lazytech-org/RIOT,msolters/RIOT,Darredevil/RIOT,Hyungsin/RIOT-OS,chris-wood/RIOT,plushvoxel/RIOT,shady33/RIOT,beurdouche/RIOT,LudwigOrtmann/RIOT,MarkXYang/RIOT,zhuoshuguo/RIOT,roberthartung/RIOT,herrfz/RIOT,beurdouche/RIOT,JensErdmann/RIOT,haoyangyu/RIOT,hamilton-mote/RIOT-OS,AnonMall/RIOT,adrianghc/RIOT,tdautc19841202/RIOT,wentaoshang/RIOT,mziegert/RIOT,abkam07/RIOT,rfswarm2/RIOT,ant9000/RIOT,AnonMall/RIOT,luciotorre/RIOT,aeneby/RIOT,latsku/RIOT,kushalsingh007/RIOT,haoyangyu/RIOT,stevenj/RIOT,FrancescoErmini/RIOT,Osblouf/RIOT,shady33/RIOT,backenklee/RIOT,FrancescoErmini/RIOT,mfrey/RIOT,arvindpdmn/RIOT,LudwigOrtmann/RIOT,d00616/RIOT,josephnoir/RIOT,d00616/RIOT,RBartz/RIOT,jasonatran/RIOT,jasonatran/RIOT,kb2ma/RIOT,kerneltask/RIOT,AnonMall/RIOT,rfswarm2/RIOT,koenning/RIOT,LudwigOrtmann/RIOT,stevenj/RIOT,backenklee/RIOT,automote/RIOT,jbeyerstedt/RIOT-OTA-update,nsol-nmsu/RIOT,neiljay/RIOT,ntrtrung/RIOT,gbarnett/RIOT,abkam07/RIOT,malosek/RIOT,BytesGalore/RIOT,RIOT-OS/RIOT,RIOT-OS/RIOT,rakendrathapa/RIOT,jhollister/RIOT,chris-wood/RIOT,MarkXYang/RIOT,dhruvvyas90/RIOT,l3nko/RIOT,AnonMall/RIOT,malosek/RIOT,bartfaizoltan/RIOT,mfrey/RIOT,kbumsik/RIOT,dhruvvyas90/RIOT,alex1818/RIOT,phiros/RIOT,PSHIVANI/Riot-Code,thiagohd/RIOT,alignan/RIOT,tfar/RIOT,biboc/RIOT,TobiasFredersdorf/RIOT,MonsterCode8000/RIOT,x3ro/RIOT,gbarnett/RIOT,tfar/RIOT,asanka-code/RIOT,Lotterleben/RIOT,centurysys/RIOT,kYc0o/RIOT,RubikonAlpha/RIOT,1blankz7/RIOT,marcosalm/RIOT,JensErdmann/RIOT,haoyangyu/RIOT,toonst/RIOT,AnonMall/RIOT,sgso/RIOT,lebrush/RIOT,ThanhVic/RIOT,beurdouche/RIOT,syin2/RIOT,luciotorre/RIOT,marcosalm/RIOT,rakendrathapa/RIOT,yogo1212/RIOT,backenklee/RIOT,DipSwitch/RIOT,mtausig/RIOT,RubikonAlpha/RIOT,malosek/RIOT,khhhh/RIOT,dkm/RIOT,Darredevil/RIOT,neumodisch/RIOT,mfrey/RIOT,1blankz7/RIOT,d00616/RIOT,MohmadAyman/RIOT,dhruvvyas90/RIOT,mziegert/RIOT,katezilla/RIOT,locicontrols/RIOT,binarylemon/RIOT,emmanuelsearch/RIOT,locicontrols/RIOT,brettswann/RIOT,jremmert-phytec-iot/RIOT,rfuentess/RIOT,jfischer-phytec-iot/RIOT,altairpearl/RIOT,openkosmosorg/RIOT,automote/RIOT,MonsterCode8000/RIOT,dhruvvyas90/RIOT,bartfaizoltan/RIOT,MarkXYang/RIOT,TobiasFredersdorf/RIOT,biboc/RIOT,kaleb-himes/RIOT,phiros/RIOT,l3nko/RIOT,DipSwitch/RIOT,kaspar030/RIOT,Lotterleben/RIOT,koenning/RIOT,MonsterCode8000/RIOT,toonst/RIOT,Darredevil/RIOT,changbiao/RIOT,mziegert/RIOT,hamilton-mote/RIOT-OS,kbumsik/RIOT,Lexandro92/RIOT-CoAP,TobiasFredersdorf/RIOT,tdautc19841202/RIOT,msolters/RIOT,openkosmosorg/RIOT,josephnoir/RIOT,tdautc19841202/RIOT,jferreir/RIOT,Hyungsin/RIOT-OS,haoyangyu/RIOT,koenning/RIOT,asanka-code/RIOT,jremmert-phytec-iot/RIOT,automote/RIOT,adjih/RIOT,marcosalm/RIOT,BytesGalore/RIOT,lebrush/RIOT,attdona/RIOT,abp719/RIOT,robixnai/RIOT,basilfx/RIOT,malosek/RIOT,jferreir/RIOT,authmillenon/RIOT,openkosmosorg/RIOT,lazytech-org/RIOT,x3ro/RIOT,Lotterleben/RIOT,gautric/RIOT,RIOT-OS/RIOT,benoit-canet/RIOT,kaspar030/RIOT,sgso/RIOT,adjih/RIOT,EmuxEvans/RIOT,zhuoshuguo/RIOT,avmelnikoff/RIOT,mtausig/RIOT,herrfz/RIOT,latsku/RIOT,RubikonAlpha/RIOT,plushvoxel/RIOT,locicontrols/RIOT,Ell-i/RIOT,stevenj/RIOT,jremmert-phytec-iot/RIOT,tfar/RIOT,kb2ma/RIOT,miri64/RIOT,marcosalm/RIOT,lazytech-org/RIOT,dailab/RIOT,brettswann/RIOT,TobiasFredersdorf/RIOT,rajma996/RIOT,Osblouf/RIOT,herrfz/RIOT,emmanuelsearch/RIOT,thomaseichinger/RIOT,authmillenon/RIOT,watr-li/RIOT,adjih/RIOT,zhuoshuguo/RIOT,beurdouche/RIOT,lebrush/RIOT,tdautc19841202/RIOT,tdautc19841202/RIOT,DipSwitch/RIOT,daniel-k/RIOT,basilfx/RIOT,EmuxEvans/RIOT,thomaseichinger/RIOT,OlegHahm/RIOT,jasonatran/RIOT,altairpearl/RIOT,shady33/RIOT,yogo1212/RIOT,miri64/RIOT,latsku/RIOT,malosek/RIOT,asanka-code/RIOT,gebart/RIOT,asanka-code/RIOT,OlegHahm/RIOT,kYc0o/RIOT,asanka-code/RIOT,fnack/RIOT,mziegert/RIOT,gbarnett/RIOT,watr-li/RIOT,robixnai/RIOT,TobiasFredersdorf/RIOT,phiros/RIOT,plushvoxel/RIOT,aeneby/RIOT,aeneby/RIOT,ant9000/RIOT,lebrush/RIOT,OlegHahm/RIOT,gbarnett/RIOT,1blankz7/RIOT,thiagohd/RIOT,robixnai/RIOT,latsku/RIOT,Josar/RIOT,syin2/RIOT,changbiao/RIOT,1blankz7/RIOT,FrancescoErmini/RIOT,x3ro/RIOT,Darredevil/RIOT,kaleb-himes/RIOT,zhuoshuguo/RIOT,rakendrathapa/RIOT,basilfx/RIOT,jfischer-phytec-iot/RIOT,locicontrols/RIOT,immesys/RiSyn,PSHIVANI/Riot-Code,LudwigOrtmann/RIOT,ros2/ros2_embedded_riot,neumodisch/RIOT,Yonezawa-T2/RIOT,authmillenon/RIOT,kb2ma/RIOT,robixnai/RIOT,bartfaizoltan/RIOT,marcosalm/RIOT,herrfz/RIOT-old,hamilton-mote/RIOT-OS,BytesGalore/PetersRIOT,MohmadAyman/RIOT,ThanhVic/RIOT,Osblouf/RIOT,automote/RIOT,LudwigKnuepfer/RIOT,Yonezawa-T2/RIOT,dailab/RIOT,BytesGalore/PetersRIOT,nsol-nmsu/RIOT,FrancescoErmini/RIOT,Josar/RIOT,rakendrathapa/RIOT,Osblouf/RIOT,OTAkeys/RIOT,robixnai/RIOT,mfrey/RIOT,rousselk/RIOT,jbeyerstedt/RIOT-OTA-update,rajma996/RIOT,thiagohd/RIOT,rousselk/RIOT,kaspar030/RIOT,zhuoshuguo/RIOT,smlng/RIOT,binarylemon/RIOT,neiljay/RIOT,binarylemon/RIOT,Yonezawa-T2/RIOT,ros2/ros2_embedded_riot,josephnoir/RIOT,jasonatran/RIOT,ros2/ros2_embedded_riot,herrfz/RIOT,MonsterCode8000/RIOT,yogo1212/RIOT,arvindpdmn/RIOT,gautric/RIOT,chris-wood/RIOT,backenklee/RIOT,msolters/RIOT,jhollister/RIOT,openkosmosorg/RIOT,RubikonAlpha/RIOT,MohmadAyman/RIOT,patkan/RIOT,automote/RIOT,dkm/RIOT,dkm/RIOT,EmuxEvans/RIOT,Hyungsin/RIOT-OS,plushvoxel/RIOT,thomaseichinger/RIOT,locicontrols/RIOT,latsku/RIOT,changbiao/RIOT,foss-for-synopsys-dwc-arc-processors/RIOT,backenklee/RIOT,changbiao/RIOT,Lotterleben/RIOT,ximus/RIOT,adjih/RIOT,arvindpdmn/RIOT,jremmert-phytec-iot/RIOT,sumanpanchal/RIOT,josephnoir/RIOT,kushalsingh007/RIOT,syin2/RIOT,fnack/RIOT,rfswarm2/RIOT,jferreir/RIOT,basilfx/RIOT,kYc0o/RIOT,mziegert/RIOT,jfischer-phytec-iot/RIOT,adrianghc/RIOT,BytesGalore/PetersRIOT,watr-li/RIOT,fnack/RIOT,neumodisch/RIOT,gbarnett/RIOT,ks156/RIOT,Lotterleben/RIOT,immesys/RiSyn,FrancescoErmini/RIOT