Shashank Sharma authored Apr 22, 2019 and Harish Krupo committed Jun 19, 2019

In order to display accurate HDR output, we need to set the
output color space of the content properly.This patch tries
to add limited control on output colorspace magagement in DRM
backend using connector's output-colorspace property.

This patch:
- Adds a new property, output colorspace, in the connector's property
  list, as well as in connector's color state (added in previos patch)
- Adds logic to set/reset/modify this property from the context of
  driving a HDR/SDR content.

This patch just adds color correction infrastructure for output
colorspace, which will be used by HDR playback scenario later in
this series. Using this infrastructure, compositor can color correct
many more scenarios involving various other cases.

V2: Addressed Pekka's review comments

Signed-off-by: Shashank Sharma <shashank.sharma@intel.com>