drm/amd/display: dp interlace MSA timing programming for Interlace mode.

[Why]
DP compliance box shows wrong MSA data.

Signed-off-by: Charlene Liu <charlene.liu@amd.com>
Reviewed-by: Jun Lei <Jun.Lei@amd.com>
Acked-by: Leo Li <sunpeng.li@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>