Add the definition to the checksum types and let mkfs accept it.
Signed-off-by: Johannes Thumshirn <jthumshirn@suse.de>
Signed-off-by: David Sterba <dsterba@suse.com>
The SHA256 is going to be used in the future, so this makes it a second
user and we also have the appropriate directory now.
Signed-off-by: David Sterba <dsterba@suse.com>