nucleo-f072rb: remove obsolete spi_divtable
nucleo-f072rb: remove obsolete spi_divtable

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