Stop bugreportd if binder call fails

Fixes: 128949427
Test: Tested by supplying a valid fd that dumpstate does not have access
to, but system server has access to. So the startBugreport call fails.
Verified that subsequent calls with proper arguments go through and not
encounter BUGREPORT_ERROR_ANOTHER_REPORT_IN_PROGRESS.

Change-Id: I393e09a4e35ae5191406112d76f27fe89418c069