mulle: add erase timings to mtd_spi_nor instance
mulle: add erase timings to mtd_spi_nor instance

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