boards/common/nrf52: revert early inclusion of Makefile.dep
boards/common/nrf52: revert early inclusion of Makefile.dep

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