drm/amd/display: Update dcn30_apply_idle_power_optimizations() code

Update the function for idle optimizations
-remove hardcoded size
-enable no memory-request case
-add cursor copy
-update mall eligibility check case

Signed-off-by: Bhawanpreet Lakha <Bhawanpreet.Lakha@amd.com>
Signed-off-by: Joshua Aberback <joshua.aberback@amd.com>
Reviewed-by: Nicholas Kazlauskas <nicholas.kazlauskas@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>