drm/omap: Implement CTM property for CRTC using OVL managers CPR matrix

Implement CTM color management property for OMAP CRTC using DSS
overlay manager's Color Phase Rotation matrix. The CPR matrix does not
exactly match the CTM property documentation. On DSS the CPR matrix is
applied after gamma table look up. However, it seems stupid to add a
custom property just for that.

Signed-off-by: Jyri Sarha <jsarha@ti.com>
Signed-off-by: Tomi Valkeinen <tomi.valkeinen@ti.com>
Reviewed-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20201103080310.164453-4-tomi.valkeinen@ti.com