Handle failure in softAp start gracefully

In the current code, if start of a softAp fails for any reason, it can
no longer start again until device boots. This is because the failure
handling misses resetting the tethering state.
This commit handles this by resetting the state on failure.

Bug: 155695448
Test: atest FrameworksWifiTests
Test: On a device that does not support 6GHz band
      $ adb shell cmd wifi start-softap kai_softap open -b 6 <==Fail
      $ adb shell cmd wifi start-softap kai_softap open -b 5 <==Succeed
Change-Id: I6b573d6d7f88ae48a63f20a20f9d4af54a87eba7
2 files changed
tree: 56e2c189265d0700e664e4f3535b9140fff8719f
  1. apex/
  2. service/
  3. metrics_pdd_hook.py
  4. PREUPLOAD.cfg