drm/amd/display: Block FPO / SubVP (DRR) on HDMI VRR configs

[Description]
- Current policy does not support HDMI VRR by default, so we
  cannot enable FPO / SubVP (DRR) cases

Reviewed-by: Nevenko Stupar <Nevenko.Stupar@amd.com>
Reviewed-by: Jun Lei <Jun.Lei@amd.com>
Acked-by: Jasdeep Dhillon <jdhillon@amd.com>
Signed-off-by: Alvin Lee <Alvin.Lee2@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>