cpu/saml21: pm: don't check individual part numbers
cpu/saml21: pm: don't check individual part numbers

Just check if the define is availiable instead.

yogo1212/RIOT,OTAkeys/RIOT,RIOT-OS/RIOT,authmillenon/RIOT,OlegHahm/RIOT,ant9000/RIOT,basilfx/RIOT,yogo1212/RIOT,OlegHahm/RIOT,OlegHahm/RIOT,authmillenon/RIOT,authmillenon/RIOT,RIOT-OS/RIOT,ant9000/RIOT,OTAkeys/RIOT,kYc0o/RIOT,jasonatran/RIOT,kYc0o/RIOT,miri64/RIOT,ant9000/RIOT,yogo1212/RIOT,kaspar030/RIOT,basilfx/RIOT,basilfx/RIOT,authmillenon/RIOT,jasonatran/RIOT,RIOT-OS/RIOT,smlng/RIOT,yogo1212/RIOT,yogo1212/RIOT,kYc0o/RIOT,kYc0o/RIOT,kaspar030/RIOT,kaspar030/RIOT,RIOT-OS/RIOT,kYc0o/RIOT,jasonatran/RIOT,smlng/RIOT,basilfx/RIOT,jasonatran/RIOT,OTAkeys/RIOT,yogo1212/RIOT,miri64/RIOT,basilfx/RIOT,miri64/RIOT,smlng/RIOT,OlegHahm/RIOT,miri64/RIOT,ant9000/RIOT,kaspar030/RIOT,authmillenon/RIOT,RIOT-OS/RIOT,miri64/RIOT,OTAkeys/RIOT,smlng/RIOT,ant9000/RIOT,kaspar030/RIOT,OTAkeys/RIOT,OlegHahm/RIOT,jasonatran/RIOT,smlng/RIOT,authmillenon/RIOT