Btrfs: pass root instead of parent_root to iterate_inode_ref

We need to pass the root that we determined earlier to iterate_inode_ref.

Reported-by: Alex Lyakas <alex.bolshoy.btrfs@gmail.com>
Signed-off-by: Alexander Block <ablock84@googlemail.com>
diff --git a/fs/btrfs/send.c b/fs/btrfs/send.c
index c6c10a4..db051d1 100644
--- a/fs/btrfs/send.c
+++ b/fs/btrfs/send.c
@@ -3206,8 +3206,8 @@
 		    found_key.type != key.type)
 			break;
 
-		ret = iterate_inode_ref(sctx, sctx->parent_root, path,
-				&found_key, 0, cb, sctx);
+		ret = iterate_inode_ref(sctx, root, path, &found_key, 0, cb,
+				sctx);
 		btrfs_release_path(path);
 		if (ret < 0)
 			goto out;