restore: don't restore cg props if task restore fails

Once the task restore has failed, we can just abort, no need to restore the cg
props.
Signed-off-by: Tycho Andersen <tycho.andersen@canonical.com>
Acked-by: Andrew Vagin <avagin@parallels.com>
Signed-off-by: Pavel Emelyanov <xemul@parallels.com>

cr-restore.c

@@ -1821,11 +1821,11 @@ int cr_restore_tasks(void)
 	if (criu_signals_setup() < 0)
 		goto err;
 
-	ret = restore_root_task(root_item);
-
-	if (prepare_cgroup_properties() < 0)
+	if (restore_root_task(root_item) < 0)
 		goto err;
 
+	ret = prepare_cgroup_properties();
+
 err:
 	fini_cgroup();
 	cr_plugin_fini();