commands: port lxc_cmd_get_init_pidfd() to new helpers

src/lxc/commands.c

@@ -590,16 +590,10 @@ static int lxc_cmd_get_init_pid_callback(int fd, struct lxc_cmd_req *req,
 int lxc_cmd_get_init_pidfd(const char *name, const char *lxcpath)
 {
 	bool stopped = false;
-	struct lxc_cmd_rr cmd = {
-		.req = {
-			.cmd = LXC_CMD_GET_INIT_PIDFD,
-		},
-		.rsp = {
-			.data = INT_TO_PTR(-EBADF),
-			.ret = ENOSYS,
-		},
-	};
 	int pidfd, ret;
+	struct lxc_cmd_rr cmd;
+
+	lxc_cmd_init(&cmd, LXC_CMD_GET_INIT_PIDFD);
 
 	ret = lxc_cmd(name, &cmd, &stopped, lxcpath, NULL);
 	if (ret < 0)