drm/amd/display: Add RMCM debug logging

[WHY & HOW]
Add new FL feature debug logging into the existing DTN logging.

Reviewed-by: Dmytro Laktyushkin <dmytro.laktyushkin@amd.com>
Reviewed-by: Charlene Liu <charlene.liu@amd.com>
Signed-off-by: Yihan Zhu <Yihan.Zhu@amd.com>
Signed-off-by: Alex Hung <alex.hung@amd.com>
Tested-by: Daniel Wheeler <daniel.wheeler@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>