drm/amd/display: add a override flag as wa for some specific dongle

[Why & How]
Add a override flag as wa for some specific dongle

Co-authored-by: Leo Chen <sancchen@amd.com>
Reviewed-by: Charlene Liu <Charlene.Liu@amd.com>
Acked-by: Brian Chang <Brian.Chang@amd.com>
Signed-off-by: Leo Chen <SanChuan.Chen@amd.com>
Tested-by: Daniel Wheeler <daniel.wheeler@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>