power: Allow devices disabling power stats completely

* On some devices even attempting to read the stats nodes results
  in kernel lockup and reboot from watchdog bite.
  This has been noticed on a lot of msm8916 devices, so add a way
  to disable stats completely in order to allow using the binderized
  power HAL and get rid of the old one from device/qcom/common

Change-Id: I134c40548dd883aaf72cf0c212be978305366521
2 files changed