core: cleanup kernel_init.c
core: cleanup kernel_init.c

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