drm/amd/display: Add work-around option to skip DCN20 clock updates

[Why] Auto Overclock Memory fails for some systems that don't support
p-state.

[How] Implement the workaround, and it's corresponding enable flag.

Signed-off-by: Jaehyun Chung <[e-mail]>
Reviewed-by: Alvin Lee <[e-mail]>
Acked-by: Leo Li <[e-mail]>
Signed-off-by: Alex Deucher <[e-mail]>

drivers/gpu/drm/amd/display/dc/clk_mgr/dcn20/dcn20_clk_mgr.c

···
 	bool force_reset = false;
 	int i;
 
+	if (dc->work_arounds.skip_clock_update)
+		return;
+
 	if (clk_mgr_base->clks.dispclk_khz == 0 ||
 		dc->debug.force_clock_mode & 0x1) {
 		//this is from resume or boot up, if forced_clock cfg option used, we bypass program dispclk and DPPCLK, but need set them for S3.

drivers/gpu/drm/amd/display/dc/dc.h

···
 	bool no_connect_phy_config;
 	bool dedcn20_305_wa;
 	struct display_mode_lib alternate_dml;
+	bool skip_clock_update;
 };
 #endif