drm/amd/display: remove TF check for LLS policy

[Why & How]
LLS policy not affected by TF.
Remove check in don't care case and use
 pixel format only.

Reviewed-by: Navid Assadian <navid.assadian@amd.com>
Signed-off-by: Samson Tam <Samson.Tam@amd.com>
Signed-off-by: Aurabindo Pillai <aurabindo.pillai@amd.com>
Tested-by: Daniel Wheeler <daniel.wheeler@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>