frdm-k64f: Define BTNx macros for user pushbuttons
frdm-k64f: Define BTNx macros for user pushbuttons

gebart/RIOT,rfuentess/RIOT,josephnoir/RIOT,lazytech-org/RIOT,x3ro/RIOT,toonst/RIOT,mtausig/RIOT,BytesGalore/RIOT,smlng/RIOT,miri64/RIOT,toonst/RIOT,ant9000/RIOT,mfrey/RIOT,smlng/RIOT,lazytech-org/RIOT,cladmi/RIOT,kaspar030/RIOT,cladmi/RIOT,yogo1212/RIOT,basilfx/RIOT,authmillenon/RIOT,authmillenon/RIOT,toonst/RIOT,OTAkeys/RIOT,mtausig/RIOT,gebart/RIOT,RIOT-OS/RIOT,miri64/RIOT,smlng/RIOT,A-Paul/RIOT,ant9000/RIOT,basilfx/RIOT,aeneby/RIOT,kaspar030/RIOT,mfrey/RIOT,miri64/RIOT,toonst/RIOT,OlegHahm/RIOT,OTAkeys/RIOT,OlegHahm/RIOT,OlegHahm/RIOT,smlng/RIOT,aeneby/RIOT,aeneby/RIOT,kaspar030/RIOT,mtausig/RIOT,yogo1212/RIOT,josephnoir/RIOT,jasonatran/RIOT,kYc0o/RIOT,RIOT-OS/RIOT,BytesGalore/RIOT,josephnoir/RIOT,basilfx/RIOT,josephnoir/RIOT,x3ro/RIOT,OTAkeys/RIOT,authmillenon/RIOT,jasonatran/RIOT,kaspar030/RIOT,rfuentess/RIOT,smlng/RIOT,A-Paul/RIOT,x3ro/RIOT,A-Paul/RIOT,kaspar030/RIOT,gebart/RIOT,rfuentess/RIOT,yogo1212/RIOT,RIOT-OS/RIOT,BytesGalore/RIOT,cladmi/RIOT,mfrey/RIOT,BytesGalore/RIOT,aeneby/RIOT,A-Paul/RIOT,lazytech-org/RIOT,rfuentess/RIOT,OTAkeys/RIOT,ant9000/RIOT,miri64/RIOT,rfuentess/RIOT,mtausig/RIOT,x3ro/RIOT,gebart/RIOT,mtausig/RIOT,authmillenon/RIOT,kYc0o/RIOT,jasonatran/RIOT,OlegHahm/RIOT,A-Paul/RIOT,authmillenon/RIOT,kYc0o/RIOT,yogo1212/RIOT,ant9000/RIOT,kYc0o/RIOT,jasonatran/RIOT,kYc0o/RIOT,basilfx/RIOT,authmillenon/RIOT,lazytech-org/RIOT,josephnoir/RIOT,aeneby/RIOT,BytesGalore/RIOT,x3ro/RIOT,basilfx/RIOT,OTAkeys/RIOT,mfrey/RIOT,toonst/RIOT,cladmi/RIOT,miri64/RIOT,lazytech-org/RIOT,cladmi/RIOT,jasonatran/RIOT,RIOT-OS/RIOT,OlegHahm/RIOT,mfrey/RIOT,yogo1212/RIOT,gebart/RIOT,yogo1212/RIOT,RIOT-OS/RIOT,ant9000/RIOT