unittests: support Makefile.include in test suites
unittests: support Makefile.include in test suites

This change will pull in the `Makefile.include` for every test suite
that is compiled in.

Fixes #1205.

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