drm/amd/display: Add config support entry to replay caps debugfs

[Why]
replay_capability debugfs tells whether sink and driver support
replay feature. However replay enablement also depends on
whether it is enabled/disabled via amdgpu module params.

[How]
Add 'Config support' entry to output current replay config.

Reviewed-by: ChiaHsuan Chung <chiahsuan.chung@amd.com>
Acked-by: Zaeem Mohamed <zaeem.mohamed@amd.com>
Signed-off-by: Roman Li <roman.li@amd.com>
Tested-by: Daniel Wheeler <daniel.wheeler@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>