drm/amd: add dc feature mask flags for PSR allow smu and multi-display optimizations

[Why]
Allow for PSR SMU optimization and PSR multiple display optimization.

[How]
Add feature flags of PSR smu optimization and PSR multiple display
optimiztaion, and set them during init sequence. By default, flags
are disabled.

Signed-off-by: David Zhang <dingchen.zhang@amd.com>
Reviewed-by: Harry Wentland <harry.wentland@amd.com>
Reviewed-by: Roman Li <Roman.Li@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>