[display][astro] Enable hardware color conversion

This CL enables hardware-based color correction. This is used to perform
various image corrections and conversion such as grayscale, etc

Also updated display-test to include separate tests for the three main
display driver (Intel, Amlogic and Mediatek)

Test: Tested on Astro and ran display-test --amlogic --grayscale
Change-Id: Id2022366c51e2ce41343d077d300c20262194eb1