hwc: Set HPD once at boot up

- HPD has to be set only once during boot up.
- This also helps in use case where HPD is turned off
  (on purpose)through by adb shell for power testing
  and on suspend/resume, it gets re-enabled.

Change-Id: I7bf6fdd08e719432029c5d6e5756685d36cdca43
3 files changed