boards/samr21-xpro: adapted uart and spi config
boards/samr21-xpro: adapted uart and spi config

adjusted names for spi and uart pad selections

gautric/RIOT,OTAkeys/RIOT,alignan/RIOT,authmillenon/RIOT,OTAkeys/RIOT,adjih/RIOT,Ell-i/RIOT,Hyungsin/RIOT-OS,jbeyerstedt/RIOT-OTA-update,kbumsik/RIOT,BytesGalore/RIOT,alignan/RIOT,Josar/RIOT,LudwigOrtmann/RIOT,smlng/RIOT,cladmi/RIOT,jbeyerstedt/RIOT-OTA-update,syin2/RIOT,backenklee/RIOT,plushvoxel/RIOT,adjih/RIOT,hamilton-mote/RIOT-OS,thomaseichinger/RIOT,katezilla/RIOT,toonst/RIOT,immesys/RiSyn,katezilla/RIOT,backenklee/RIOT,thomaseichinger/RIOT,Josar/RIOT,neiljay/RIOT,mfrey/RIOT,OlegHahm/RIOT,neiljay/RIOT,biboc/RIOT,RIOT-OS/RIOT,basilfx/RIOT,avmelnikoff/RIOT,kbumsik/RIOT,dailab/RIOT,toonst/RIOT,gebart/RIOT,dailab/RIOT,foss-for-synopsys-dwc-arc-processors/RIOT,ant9000/RIOT,jasonatran/RIOT,kaleb-himes/RIOT,kaleb-himes/RIOT,alignan/RIOT,immesys/RiSyn,RIOT-OS/RIOT,miri64/RIOT,OlegHahm/RIOT,cladmi/RIOT,kaspar030/RIOT,cladmi/RIOT,Hyungsin/RIOT-OS,foss-for-synopsys-dwc-arc-processors/RIOT,beurdouche/RIOT,kerneltask/RIOT,BytesGalore/RIOT,neiljay/RIOT,roberthartung/RIOT,syin2/RIOT,jfischer-phytec-iot/RIOT,smlng/RIOT,neumodisch/RIOT,LudwigOrtmann/RIOT,backenklee/RIOT,RIOT-OS/RIOT,ks156/RIOT,backenklee/RIOT,A-Paul/RIOT,yogo1212/RIOT,neumodisch/RIOT,kbumsik/RIOT,mfrey/RIOT,Ell-i/RIOT,LudwigOrtmann/RIOT,authmillenon/RIOT,mtausig/RIOT,hamilton-mote/RIOT-OS,beurdouche/RIOT,TobiasFredersdorf/RIOT,jasonatran/RIOT,kYc0o/RIOT,thomaseichinger/RIOT,lazytech-org/RIOT,BytesGalore/RIOT,kYc0o/RIOT,ks156/RIOT,kYc0o/RIOT,katezilla/RIOT,gebart/RIOT,adjih/RIOT,gautric/RIOT,josephnoir/RIOT,kbumsik/RIOT,josephnoir/RIOT,syin2/RIOT,rfuentess/RIOT,LudwigOrtmann/RIOT,kb2ma/RIOT,adrianghc/RIOT,jfischer-phytec-iot/RIOT,smlng/RIOT,Hyungsin/RIOT-OS,OTAkeys/RIOT,biboc/RIOT,A-Paul/RIOT,aeneby/RIOT,alignan/RIOT,Hyungsin/RIOT-OS,kb2ma/RIOT,TobiasFredersdorf/RIOT,mfrey/RIOT,jasonatran/RIOT,RIOT-OS/RIOT,jbeyerstedt/RIOT-OTA-update,smlng/RIOT,gautric/RIOT,immesys/RiSyn,adrianghc/RIOT,kYc0o/RIOT,mtausig/RIOT,tfar/RIOT,avmelnikoff/RIOT,kerneltask/RIOT,lazytech-org/RIOT,basilfx/RIOT,Ell-i/RIOT,TobiasFredersdorf/RIOT,kb2ma/RIOT,ant9000/RIOT,Josar/RIOT,roberthartung/RIOT,mtausig/RIOT,jfischer-phytec-iot/RIOT,yogo1212/RIOT,rfuentess/RIOT,tfar/RIOT,LudwigKnuepfer/RIOT,kaleb-himes/RIOT,authmillenon/RIOT,jbeyerstedt/RIOT-OTA-update,ks156/RIOT,immesys/RiSyn,x3ro/RIOT,katezilla/RIOT,TobiasFredersdorf/RIOT,thomaseichinger/RIOT,cladmi/RIOT,plushvoxel/RIOT,OlegHahm/RIOT,yogo1212/RIOT,josephnoir/RIOT,BytesGalore/RIOT,plushvoxel/RIOT,immesys/RiSyn,avmelnikoff/RIOT,jfischer-phytec-iot/RIOT,hamilton-mote/RIOT-OS,rfuentess/RIOT,syin2/RIOT,tfar/RIOT,authmillenon/RIOT,josephnoir/RIOT,LudwigKnuepfer/RIOT,authmillenon/RIOT,beurdouche/RIOT,gebart/RIOT,Hyungsin/RIOT-OS,josephnoir/RIOT,rfuentess/RIOT,avmelnikoff/RIOT,RIOT-OS/RIOT,ant9000/RIOT,beurdouche/RIOT,kbumsik/RIOT,jfischer-phytec-iot/RIOT,adjih/RIOT,thomaseichinger/RIOT,OlegHahm/RIOT,avmelnikoff/RIOT,mfrey/RIOT,Josar/RIOT,smlng/RIOT,plushvoxel/RIOT,katezilla/RIOT,x3ro/RIOT,adrianghc/RIOT,yogo1212/RIOT,hamilton-mote/RIOT-OS,adjih/RIOT,cladmi/RIOT,biboc/RIOT,jasonatran/RIOT,Ell-i/RIOT,hamilton-mote/RIOT-OS,x3ro/RIOT,kerneltask/RIOT,OlegHahm/RIOT,kerneltask/RIOT,toonst/RIOT,LudwigKnuepfer/RIOT,mfrey/RIOT,tfar/RIOT,lazytech-org/RIOT,gebart/RIOT,kaleb-himes/RIOT,dailab/RIOT,foss-for-synopsys-dwc-arc-processors/RIOT,ant9000/RIOT,miri64/RIOT,rfuentess/RIOT,kb2ma/RIOT,neumodisch/RIOT,kaspar030/RIOT,dkm/RIOT,foss-for-synopsys-dwc-arc-processors/RIOT,ks156/RIOT,jasonatran/RIOT,kerneltask/RIOT,TobiasFredersdorf/RIOT,biboc/RIOT,roberthartung/RIOT,foss-for-synopsys-dwc-arc-processors/RIOT,neiljay/RIOT,neiljay/RIOT,alignan/RIOT,kaspar030/RIOT,aeneby/RIOT,gautric/RIOT,ant9000/RIOT,yogo1212/RIOT,miri64/RIOT,syin2/RIOT,Ell-i/RIOT,mtausig/RIOT,kYc0o/RIOT,LudwigOrtmann/RIOT,kaspar030/RIOT,gautric/RIOT,adrianghc/RIOT,Josar/RIOT,lazytech-org/RIOT,neumodisch/RIOT,OTAkeys/RIOT,miri64/RIOT,miri64/RIOT,toonst/RIOT,plushvoxel/RIOT,authmillenon/RIOT,LudwigOrtmann/RIOT,LudwigKnuepfer/RIOT,dkm/RIOT,adrianghc/RIOT,basilfx/RIOT,x3ro/RIOT,roberthartung/RIOT,kaspar030/RIOT,basilfx/RIOT,aeneby/RIOT,lazytech-org/RIOT,x3ro/RIOT,dkm/RIOT,backenklee/RIOT,mtausig/RIOT,basilfx/RIOT,A-Paul/RIOT,gebart/RIOT,kb2ma/RIOT,A-Paul/RIOT,beurdouche/RIOT,yogo1212/RIOT,OTAkeys/RIOT,biboc/RIOT,neumodisch/RIOT,neumodisch/RIOT,tfar/RIOT,jbeyerstedt/RIOT-OTA-update,dailab/RIOT,aeneby/RIOT,dailab/RIOT,kaleb-himes/RIOT,toonst/RIOT,dkm/RIOT,roberthartung/RIOT,aeneby/RIOT,dkm/RIOT,A-Paul/RIOT,BytesGalore/RIOT,LudwigKnuepfer/RIOT,immesys/RiSyn,ks156/RIOT