Pekka Paalanen authored May 03, 2022 and Pekka Paalanen committed May 27, 2022

This is the beginnings of creating composited content HDR metadata for
the ST2084 HDR mode. The immediate goal is to allow essentially setting
the HDR metadata from weston.ini, so that it can be experimented with.

Setting an output ICC profile will stop weston.ini metadata from taking
effect, but using an ICC profile in HDR mode is an open question anyway.

maxDML, maxCLL, and minDML are set based on the assumption that we want
to make use of the full sink/monitor dynamic range.

This also adds several TODOs about how we should handle output profiles,
basic output color characteristics, and HDR metadata. Implementing these
properly will take more thought and effort.

Signed-off-by: Pekka Paalanen <pekka.paalanen@collabora.com>