conman: survive QCSAPI failures.

QCSAPI occasionally fails for a yet-unknown reason. conman treats the
CalledProcessError as a None result, which is fed into the FrenzyWPACtrl
state machine. This can lead to spurious state transitions. Instead,
skip the update if QCSAPI fails.

Change-Id: I6f248e6ce012b31c9b8044b090a71592e694621c
2 files changed