ocfs2/quota: Release lock for error in ocfs2_quota_write.

ocfs2_quota_write needs to release the lock if it fails to
read quota block. So use "goto out" instead of "return err".

Signed-off-by: Tao Ma <tao.ma@oracle.com>
Acked-by: Jan Kara <jack@suse.cz>
Signed-off-by: Joel Becker <joel.becker@oracle.com>
diff --git a/fs/ocfs2/quota_global.c b/fs/ocfs2/quota_global.c
index cc8785c..d604a6a 100644
--- a/fs/ocfs2/quota_global.c
+++ b/fs/ocfs2/quota_global.c
@@ -238,7 +238,7 @@
 	}
 	if (err) {
 		mlog_errno(err);
-		return err;
+		goto out;
 	}
 	lock_buffer(bh);
 	if (new)