UBIFS: return proper error code if the compr is not present

If the compressor is not present, mount_ubifs need
to return an error code. This way ubifs_fill_super
will stop and handle the error.
Signed-off-by: NCorentin Chary <corentincj@iksaif.net>
Signed-off-by: NArtem Bityutskiy <Artem.Bityutskiy@nokia.com>

fs/ubifs/super.c

@@ -1187,6 +1187,7 @@ static int mount_ubifs(struct ubifs_info *c)
 	if (!ubifs_compr_present(c->default_compr)) {
 		ubifs_err("'compressor \"%s\" is not compiled in",
 			  ubifs_compr_name(c->default_compr));
+		err = -ENOTSUPP;
 		goto out_free;
 	}