drm/amd/display: Add interface to capture power feature status for debug logging

drm/amd/display: Add interface to capture power feature status for debug logging

[Why]
The status of various power features is often important information when
debugging certain issues, such as underflow. This info helps to
narrow down the potential sources of errors.

[How]
Add dc interface to capture power feature enablement status.

Reviewed-by: Dillon Varone <dillon.varone@amd.com>
Signed-off-by: George Shen <george.shen@amd.com>
Signed-off-by: Fangzhi Zuo <jerry.zuo@amd.com>
Tested-by: Dan Wheeler <daniel.wheeler@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>