drm/amd/display : add high part address calculation for underlay

Currently the high part of the address structure is not
populated in case of luma and chroma.
This patch adds this calculation.

Signed-off-by: Shirish S <shirish.s@amd.com>
Reviewed-by: Alex Deucher <alexander.deucher@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>