suit/storage/flashwrite: Add flashpage_raw capability
suit/storage/flashwrite: Add flashpage_raw capability

Updates the suit flashwrite storage module to include compatibility with
the riotboot flashwrite raw capability.

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