drm/amd/display: Use VCP for extended colorimetry

DPRX should send the VCP extended colorimetry packet if the
sink supports DPCD rev1.4 and reports the extended colorimetry
bit.

Signed-off-by: Aric Cyr <aric.cyr@amd.com>
Reviewed-by: Anthony Koo <Anthony.Koo@amd.com>
Acked-by: Bhawanpreet Lakha <Bhawanpreet.Lakha@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>