btrfs: cleanup error handling in btrfs_unlink_inode()

When btrfs_alloc_path() fails, btrfs_free_path() need not be called.
Therefore, it changes the branch ahead.

Signed-off-by: Tsutomu Itoh <t-itoh@jp.fujitsu.com>
Signed-off-by: Chris Mason <chris.mason@oracle.com>
diff --git a/fs/btrfs/inode.c b/fs/btrfs/inode.c
index 36bc3f4..c9bc0af 100644
--- a/fs/btrfs/inode.c
+++ b/fs/btrfs/inode.c
@@ -2646,7 +2646,7 @@
 	path = btrfs_alloc_path();
 	if (!path) {
 		ret = -ENOMEM;
-		goto err;
+		goto out;
 	}
 
 	path->leave_spinning = 1;