sdm: Use LayerRequests in Tonemapper.

- Make use of the LayerRequests set by SDM in HWC
  Tonemapper to configure the Layer Information.
- Helps in handling format change when tonemapping
  from YUV to RGB
- Includes some changes needed in buffer allocator
  and sync handler

Change-Id: I105116a7fe718e68329b17a209e37be399a6f8ca
Crs-fixed: 1106036
5 files changed