hwc2: Add support to disable HDR handling

- Set "sys.hwc_disable_hdr" to 1 to disable HDR handling
  in HAL.
- On setting that property, a HDR layer will be treated
  as a regular layer.

Change-Id: I98b9896c12f55f4591a519d9896b24409879e0ae
Crs-fixed: 2051634
2 files changed