UBIFS: fix remount error path

Dan's "smatch" checker found out that there was a bug in the error path of the
'ubifs_remount_rw()' function. Instead of jumping to the "out" label which
cleans-things up, we just returned.

This patch fixes the problem.

Reported-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Artem Bityutskiy <artem.bityutskiy@linux.intel.com>
diff --git a/fs/ubifs/super.c b/fs/ubifs/super.c
index a126608..a81c7b5 100644
--- a/fs/ubifs/super.c
+++ b/fs/ubifs/super.c
@@ -1556,7 +1556,7 @@
 	if (c->space_fixup) {
 		err = ubifs_fixup_free_space(c);
 		if (err)
-			return err;
+			goto out;
 	}
 
 	err = check_free_space(c);