drm/amd/display: Add debug prints for IPS testing

[WHY]
To log commit states and when we transition in/out of allow and idle
states and the caller.

[HOW]
Add a new logging helper and wrap idle optimization calls to receive
the caller.

Reviewed-by: Duncan Ma <duncan.ma@amd.com>
Acked-by: Alex Hung <alex.hung@amd.com>
Signed-off-by: Nicholas Kazlauskas <nicholas.kazlauskas@amd.com>
Tested-by: Daniel Wheeler <daniel.wheeler@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>