drm/amd/display: Don't set dram clock change requirement for SubVP

[Description]
In general cases we want to keep the dram clock change requirement (we
prefer configs that support MCLK switch). Only override to false for
SubVP.

Reviewed-by: Jun Lei <[e-mail]>
Acked-by: Rodrigo Siqueira <[e-mail]>
Signed-off-by: Alvin Lee <[e-mail]>
Tested-by: Daniel Wheeler <[e-mail]>
Signed-off-by: Alex Deucher <[e-mail]>

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

···
 	double max_avg_fabric_bw_use_normal_percent;
 	double max_avg_dram_bw_use_normal_strobe_percent;
 	enum dm_prefetch_modes allow_for_pstate_or_stutter_in_vblank_final;
+	bool dram_clock_change_requirement_final;
 	double writeback_latency_us;
 	double ideal_dram_bw_after_urgent_percent;
 	double pct_ideal_dram_sdp_bw_after_urgent_pixel_only; // PercentOfIdealDRAMFabricAndSDPPortBWReceivedAfterUrgLatencyPixelDataOnly

drivers/gpu/drm/amd/display/dc/dml/display_mode_vba.c

···
 	mode_lib->vba.MaxAveragePercentOfIdealDRAMBWDisplayCanUseInNormalSystemOperationSTROBE =
 			soc->max_avg_dram_bw_use_normal_strobe_percent;
 
-	mode_lib->vba.DRAMClockChangeRequirementFinal = 1;
+	mode_lib->vba.DRAMClockChangeRequirementFinal = soc->dram_clock_change_requirement_final;
 	mode_lib->vba.FCLKChangeRequirementFinal = 1;
 	mode_lib->vba.USRRetrainingRequiredFinal = 1;
 	mode_lib->vba.ConfigurableDETSizeEnFinal = 0;