drm/amd/display: Allow clock lower on dce100

dce100 was set to always pass safe_to_lower = false
to the clock manager

Thus, on suspend the clocks were not being set to 0
which is incorrect behaviour

This was causing s3 resume to blackscreen on intel
CPUs with dce100 GPUs attached

(Note that the hash in this Fixes: tag is the hash on Alex's tree)
Fixes: ae7d8aeb38d7 ("drm/amd/display: remove safe_to_lower flag from dc, use 2 functions instead")
Signed-off-by: David Francis <David.Francis@amd.com>
Reviewed-by: Harry Wentland <Harry.Wentland@amd.com>
Acked-by: Leo Li <sunpeng.li@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>

drivers/gpu/drm/amd/display/dc/dce100/dce100_hw_sequencer.c

@@ -117,6 +117,18 @@ void dce100_prepare_bandwidth(
 			false);
 }
 
+void dce100_optimize_bandwidth(
+		struct dc *dc,
+		struct dc_state *context)
+{
+	dce110_set_safe_displaymarks(&context->res_ctx, dc->res_pool);
+
+	dc->res_pool->clk_mgr->funcs->update_clocks(
+			dc->res_pool->clk_mgr,
+			context,
+			true);
+}
+
 /**************************************************************************/
 
 void dce100_hw_sequencer_construct(struct dc *dc)
@@ -125,6 +137,6 @@ void dce100_hw_sequencer_construct(struct dc *dc)
 
 	dc->hwss.enable_display_power_gating = dce100_enable_display_power_gating;
 	dc->hwss.prepare_bandwidth = dce100_prepare_bandwidth;
-	dc->hwss.optimize_bandwidth = dce100_prepare_bandwidth;
+	dc->hwss.optimize_bandwidth = dce100_optimize_bandwidth;
 }