[Why]
We want to get the visual confirm color of the bottom-most pipe
for test automation.

[How]
Save the visual confirm color to plane_state before program to MPC;
Reviewed-by: NAnthony Koo <Anthony.Koo@amd.com>
Reviewed-by: NAric Cyr <Aric.Cyr@amd.com>
Acked-by: NBrian Chang <Brian.Chang@amd.com>
Signed-off-by: NLeo (Hanghong) Ma <hanghong.ma@amd.com>
Tested-by: NDaniel Wheeler <daniel.wheeler@amd.com>
Signed-off-by: NAlex Deucher <alexander.deucher@amd.com>