drm/amd/display: Add COLOR_ENCODING/COLOR_RANGE to overlay planes

drm/amd/display: Add COLOR_ENCODING/COLOR_RANGE to overlay planes

Extend COLOR_ENCODING and COLOR_RANGE property creation to overlay
planes in addition to primary planes. This allows overlay planes to
use YUV formats with proper color space configuration when the
hardware supports NV12/P010 formats.

These properties control the YUV-to-RGB conversion matrix selection
(BT.601/BT.709/BT.2020) and range handling (limited/full range).

Assisted-by: Claude: claude-sonnet-4.5
Reviewed-by: Alex Hung <alex.hung@amd.com>
Signed-off-by: Harry Wentland <harry.wentland@amd.com>
Signed-off-by: Alex Hung <alex.hung@amd.com>
Tested-by: Dan Wheeler <daniel.wheeler@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>