[Why]
Add necessary support for Freesync HDMI in Linux DM
[How]
- Support Freesync HDMI by calling DC interace
- Report Freesync capability to vrr_range debugfs from DRM
- Depends on coming DMCU/DMUB firmware to enable feature
Signed-off-by: Stylon Wang <stylon.wang@amd.com> Reviewed-by: Nicholas Kazlauskas <Nicholas.Kazlauskas@amd.com> Acked-by: Qingqing Zhuo <Qingqing.Zhuo@amd.com> Tested-by: Daniel Wheeler <daniel.wheeler@amd.com> Signed-off-by: Alex Deucher <alexander.deucher@amd.com>