drm/amd/display: Select correct DTO source

[WHY&HOW]
Change criteria for setting DTO source value, and always set it regardless of
the signal type.
Reviewed-by: Ariel Bernstein <Eric.Bernstein@amd.com>
Acked-by: Pavle Kotarac <Pavle.Kotarac@amd.com>
Signed-off-by: Dillon Varone <dillon.varone@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>

drivers/gpu/drm/amd/display/dc/dce/dce_clock_source.c

@@ -985,7 +985,7 @@ static bool dcn31_program_pix_clk(
 	struct bp_pixel_clock_parameters bp_pc_params = {0};
 	enum transmitter_color_depth bp_pc_colour_depth = TRANSMITTER_COLOR_DEPTH_24;
 	// For these signal types Driver to program DP_DTO without calling VBIOS Command table
-	if (dc_is_dp_signal(pix_clk_params->signal_type)) {
+	if (dc_is_dp_signal(pix_clk_params->signal_type) || dc_is_virtual_signal(pix_clk_params->signal_type)) {
 		if (e) {
 			/* Set DTO values: phase = target clock, modulo = reference clock*/
 			REG_WRITE(PHASE[inst], e->target_pixel_rate_khz * e->mult_factor);