Recover cleanly from power HAL service crashes

Recover cleanly from power HAL service crashes

Currently if the binderized power HAL service crashes, services that
call the HAL will crash as well. To fix this:
- Before calling power HAL functions, check that the handle to the
  power HAL service is still valid, and reload using getService() if
  necessary.
- When a call to a power HAL function fails, log the failure and mark
  the handle as invalid.

Bug: 35728909
Test: adb shell kill -9 $(adb shell pidof android.hardware.power@1.0-service)
Change-Id: Id2dd1a6507b9f5044d928483cdb6b736c701f8ba
Signed-off-by: Connor O'Brien <connoro@google.com>