btrfs: fix lost error handling when replaying directory deletes

At replay_dir_deletes(), if find_dir_range() returns an error we break out
of the main while loop and then assign a value of 0 (success) to the 'ret'
variable, resulting in completely ignoring that an error happened. Fix
that by jumping to the 'out' label when find_dir_range() returns an error
(negative value).

CC: stable@vger.kernel.org # 4.4+
Reviewed-by: Josef Bacik <josef@toxicpanda.com>
Signed-off-by: Filipe Manana <fdmanana@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>

fs/btrfs/tree-log.c

@@ -2528,7 +2528,9 @@ again:
 		else {
 			ret = find_dir_range(log, path, dirid, key_type,
 					     &range_start, &range_end);
-			if (ret != 0)
+			if (ret < 0)
+				goto out;
+			else if (ret > 0)
 				break;
 		}