drm/amd/display: FVA timing adjustment

[why]
need to add timing adjustment for fva.

[how]
add hook to optc and hwseq.

Acked-by: Alan Liu <HaoPing.Liu@amd.com>
Signed-off-by: Charlene Liu <Charlene.Liu@amd.com>
Tested-by: Daniel Wheeler <daniel.wheeler@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>