cpu/samd21: add gpio support for samr21e18a
cpu/samd21: add gpio support for samr21e18a

jasonatran/RIOT,basilfx/RIOT,x3ro/RIOT,LudwigOrtmann/RIOT,hamilton-mote/RIOT-OS,immesys/RiSyn,gebart/RIOT,roberthartung/RIOT,kaspar030/RIOT,kaspar030/RIOT,roberthartung/RIOT,kaspar030/RIOT,beurdouche/RIOT,RIOT-OS/RIOT,authmillenon/RIOT,smlng/RIOT,authmillenon/RIOT,yogo1212/RIOT,biboc/RIOT,yogo1212/RIOT,adjih/RIOT,cladmi/RIOT,cladmi/RIOT,yogo1212/RIOT,rfuentess/RIOT,basilfx/RIOT,authmillenon/RIOT,biboc/RIOT,plushvoxel/RIOT,Josar/RIOT,roberthartung/RIOT,basilfx/RIOT,kbumsik/RIOT,hamilton-mote/RIOT-OS,plushvoxel/RIOT,A-Paul/RIOT,OTAkeys/RIOT,OlegHahm/RIOT,RIOT-OS/RIOT,A-Paul/RIOT,kerneltask/RIOT,adjih/RIOT,Josar/RIOT,yogo1212/RIOT,miri64/RIOT,jasonatran/RIOT,Josar/RIOT,authmillenon/RIOT,toonst/RIOT,kbumsik/RIOT,roberthartung/RIOT,adrianghc/RIOT,hamilton-mote/RIOT-OS,cladmi/RIOT,A-Paul/RIOT,OlegHahm/RIOT,neiljay/RIOT,miri64/RIOT,OTAkeys/RIOT,lazytech-org/RIOT,neiljay/RIOT,kYc0o/RIOT,jasonatran/RIOT,ant9000/RIOT,mfrey/RIOT,ks156/RIOT,yogo1212/RIOT,avmelnikoff/RIOT,LudwigKnuepfer/RIOT,mtausig/RIOT,kbumsik/RIOT,adrianghc/RIOT,adrianghc/RIOT,LudwigKnuepfer/RIOT,aeneby/RIOT,LudwigOrtmann/RIOT,jasonatran/RIOT,authmillenon/RIOT,ks156/RIOT,thomaseichinger/RIOT,A-Paul/RIOT,BytesGalore/RIOT,aeneby/RIOT,adrianghc/RIOT,thomaseichinger/RIOT,josephnoir/RIOT,mtausig/RIOT,OlegHahm/RIOT,mfrey/RIOT,BytesGalore/RIOT,plushvoxel/RIOT,miri64/RIOT,neiljay/RIOT,josephnoir/RIOT,mtausig/RIOT,BytesGalore/RIOT,avmelnikoff/RIOT,ant9000/RIOT,basilfx/RIOT,plushvoxel/RIOT,LudwigKnuepfer/RIOT,aeneby/RIOT,hamilton-mote/RIOT-OS,authmillenon/RIOT,adjih/RIOT,adjih/RIOT,mtausig/RIOT,ant9000/RIOT,LudwigOrtmann/RIOT,avmelnikoff/RIOT,OTAkeys/RIOT,ant9000/RIOT,lazytech-org/RIOT,miri64/RIOT,avmelnikoff/RIOT,RIOT-OS/RIOT,x3ro/RIOT,beurdouche/RIOT,adrianghc/RIOT,A-Paul/RIOT,avmelnikoff/RIOT,RIOT-OS/RIOT,beurdouche/RIOT,Josar/RIOT,toonst/RIOT,OTAkeys/RIOT,rfuentess/RIOT,neiljay/RIOT,ant9000/RIOT,immesys/RiSyn,OTAkeys/RIOT,kaspar030/RIOT,kYc0o/RIOT,kYc0o/RIOT,rfuentess/RIOT,kaspar030/RIOT,hamilton-mote/RIOT-OS,kYc0o/RIOT,gebart/RIOT,gebart/RIOT,x3ro/RIOT,kerneltask/RIOT,gebart/RIOT,smlng/RIOT,LudwigOrtmann/RIOT,RIOT-OS/RIOT,LudwigKnuepfer/RIOT,beurdouche/RIOT,smlng/RIOT,immesys/RiSyn,ks156/RIOT,basilfx/RIOT,rfuentess/RIOT,x3ro/RIOT,LudwigKnuepfer/RIOT,kbumsik/RIOT,OlegHahm/RIOT,cladmi/RIOT,josephnoir/RIOT,josephnoir/RIOT,kerneltask/RIOT,kYc0o/RIOT,toonst/RIOT,neiljay/RIOT,thomaseichinger/RIOT,immesys/RiSyn,ks156/RIOT,yogo1212/RIOT,roberthartung/RIOT,lazytech-org/RIOT,lazytech-org/RIOT,miri64/RIOT,immesys/RiSyn,gebart/RIOT,BytesGalore/RIOT,kerneltask/RIOT,biboc/RIOT,mfrey/RIOT,aeneby/RIOT,adjih/RIOT,mtausig/RIOT,lazytech-org/RIOT,mfrey/RIOT,jasonatran/RIOT,smlng/RIOT,toonst/RIOT,OlegHahm/RIOT,x3ro/RIOT,Josar/RIOT,ks156/RIOT,LudwigOrtmann/RIOT,thomaseichinger/RIOT,immesys/RiSyn,smlng/RIOT,plushvoxel/RIOT,kerneltask/RIOT,cladmi/RIOT,toonst/RIOT,beurdouche/RIOT,rfuentess/RIOT,biboc/RIOT,kbumsik/RIOT,aeneby/RIOT,mfrey/RIOT,BytesGalore/RIOT,biboc/RIOT,LudwigOrtmann/RIOT,josephnoir/RIOT,thomaseichinger/RIOT