drm/amd/display: Disable PG on NV12

[Why]
HW team request to disable PG on NV12 (fixing missed cases)

[How]
Disable dpp and hubp PG

Signed-off-by: Alvin Lee <alvin.lee2@amd.com>
Reviewed-by: Aric Cyr <Aric.Cyr@amd.com>
Acked-by: Qingqing Zhuo <qingqing.zhuo@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>