coverity: preserve_ns returns bool, not int

src/lxc/start.c

@@ -1060,8 +1060,7 @@ static int lxc_spawn(struct lxc_handler *handler)
 		goto out_delete_net;
 	}
 
-	if (preserve_ns(handler->nsfd, handler->clone_flags, handler->pid,
-				&errmsg) < 0) {
+	if (!preserve_ns(handler->nsfd, handler->clone_flags, handler->pid, &errmsg)) {
 		INFO("Failed to store namespace references for stop hook: %s",
 			errmsg ? errmsg : "(Out of memory)");
 		free(errmsg);