Merge #405 into sdk602patch0521 from refs/changes/405/head

Merge #405 into sdk602patch0521 from refs/changes/405/head

Code review from 袁清梦

* refs/changes/405/head: (3 commits squashed)

  - 增加恢复出厂设置AT  AT^RESTORE

  - Merge branch 'sdk602patch0521' of https://codeup.aliyun.com/64191456b9581d62e8f81ac0/FD230 into sdk602patch0521

  - Merge branch 'sdk602patch0521' of https://codeup.aliyun.com/64191456b9581d62e8f81ac0/FD230 into sdk602patch0521

Signed-off-by: Caisking <3449750381@qq.com>
Reviewed-by: snickersun@163.com <accounts_62b90f7fcf51ade33b6f628e@mail.teambition.com>
Merged-by: snickersun@163.com <accounts_62b90f7fcf51ade33b6f628e@mail.teambition.com>
link: https://codeup.aliyun.com/64191456b9581d62e8f81ac0/FD230/change/405