bdrv_move_feature_fields() and swap_feature_fields() are empty now, they
can be removed.
Signed-off-by: NKevin Wolf <kwolf@redhat.com>
Reviewed-by: NMax Reitz <mreitz@redhat.com>
Reviewed-by: NAlberto Garcia <berto@igalia.com>
Acked-by: NStefan Hajnoczi <stefanha@redhat.com>