boards/nf51dongle: use common clock config
boards/nf51dongle: use common clock config

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