drm/amd/display: Remove redundant idle optimization check

[Why]
Disable idle optimization for each atomic commit is unnecessary,
and can lead to a potential race condition.

[How]
Remove idle optimization check from amdgpu_dm_atomic_commit_tail()

Fixes: 196107eb ("drm/amd/display: Add IPS checks before dcn register access")
Cc: stable@vger.kernel.org
Reviewed-by: Hamza Mahfooz <hamza.mahfooz@amd.com>
Acked-by: Roman Li <roman.li@amd.com>
Signed-off-by: Roman Li <roman.li@amd.com>
Tested-by: Daniel Wheeler <daniel.wheeler@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>

drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.c

@@ -9169,9 +9169,6 @@ static void amdgpu_dm_atomic_commit_tail(struct drm_atomic_state *state)
 
 	trace_amdgpu_dm_atomic_commit_tail_begin(state);
 
-	if (dm->dc->caps.ips_support && dm->dc->idle_optimizations_allowed)
-		dc_allow_idle_optimizations(dm->dc, false);
-
 	drm_atomic_helper_update_legacy_modeset_state(dev, state);
 	drm_dp_mst_atomic_wait_for_dependencies(state);