restore: die properly if restore_one_task fails

This is really just the last bit of c32046c9; if restore_one_task() fails, we
need to do the same futex wakeup we do everywhere else in this function.

v2: use err instead of err_fini_mnt after mount has been finalized normally
Signed-off-by: Tycho Andersen <tycho.andersen@canonical.com>
Acked-by: Acked-by: Andrew Vagin <avagin@parallels.com>
Signed-off-by: Pavel Emelyanov <xemul@parallels.com>

cr-restore.c

@@ -1465,9 +1465,12 @@ static int restore_task_with_children(void *_arg)
 		goto err_fini_mnt;
 
 	if (current->parent == NULL && fini_mnt_ns())
-		goto err_fini_mnt;
+		goto err;
 
-	return restore_one_task(current->pid.virt, ca->core);
+	if (restore_one_task(current->pid.virt, ca->core))
+		goto err;
+
+	return 0;
 
 err_fini_mnt:
 	if (current->parent == NULL)