Sensors: MultiHal: ignore errors from poll calls

Sensors: MultiHal: ignore errors from poll calls

MultiHal was not properly fielding errors from the poll() calls of
sub-HALs.  Propagating errors received from sub-HALs up to Sensor
Services causes Sensor Services to abort, so instead of propagating
the error up to Sensor Services, the MultiHal logs a message to
logcat to fix the sub-HAL problem.

Bug: 30060537
Change-Id: I6e20c193a2f2d228da48cf3d5a23e439eaf663df