[HWC] Add setLayerFloatColor API.

This patch adds the struct of float color, and setLayerFloatColor API so that
SurfaceFlinger can set the layer color with more bits on each channel.
Currently the display calibration tool require 10-bits support.

BUG: 69970838
Test: make locally and applied on device
Change-Id: I8bab335cc4fbc41a3eb18306a8831d1e9a9a219a
2 files changed