Support fp16 in sf

* Make sure we don't dim SDR in renderengine, and instead map HDR to the
  correct relative luminance above 1.0
* Plumb the HDR/SDR ratio into HWC

Bug: 236745178
Test: builds
Change-Id: I325972a01280d287189d38dd6c5bf7f2d4b776bb
36 files changed