drm/amd/display: Blocking invalid 420 modes on HDMI TMDS for DCN314

[Why & How]
HDMI TMDS does not have ODM support. Filtering 420 modes that
exceed the 4096 FMT limitation on DCN314 will resolve
intermittent corruptions issues.

Reviewed-by: Nicholas Kazlauskas <nicholas.kazlauskas@amd.com>
Acked-by: Tom Chung <chiahsuan.chung@amd.com>
Signed-off-by: Leo Chen <sancchen@amd.com>
Tested-by: Daniel Wheeler <daniel.wheeler@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>