drm/amd/display: Fix HSplit causing increase in DSC Slice Count

[Why?]
HSplit should not affect DSC slice count. Can cause improper timings to
be applied for certain modes.

[How?]
No longer change DSC Slice count based on HSplit.
Tested-by: Daniel Wheeler <daniel.wheeler@amd.com>
Signed-off-by: Dillon Varone <dillon.varone@amd.com>
Reviewed-by: Dmytro Laktyushkin <Dmytro.Laktyushkin@amd.com>
Acked-by: Rodrigo Siqueira <Rodrigo.Siqueira@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>

drivers/gpu/drm/amd/display/dc/dml/dcn30/display_mode_vba_30.c

@@ -4050,7 +4050,7 @@ void dml30_ModeSupportAndSystemConfigurationFull(struct display_mode_lib *mode_l
 					v->RequiredDPPCLK[i][j][NumberOfNonSplitPlaneOfMaximumBandwidth] = v->MinDPPCLKUsingSingleDPP[NumberOfNonSplitPlaneOfMaximumBandwidth]
 							* (1 + v->DISPCLKDPPCLKDSCCLKDownSpreading / 100) / 2;
 					v->TotalNumberOfActiveDPP[i][j] = v->TotalNumberOfActiveDPP[i][j] + 1;
-					v->TotalNumberOfSingleDPPPlanes[i][j] = v->TotalNumberOfSingleDPPPlanes[i][j] + 1;
+					v->TotalNumberOfSingleDPPPlanes[i][j] = v->TotalNumberOfSingleDPPPlanes[i][j] - 1;
 				}
 			}
 			if (v->TotalNumberOfActiveDPP[i][j] > v->MaxNumDPP) {

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

@@ -599,7 +599,6 @@ static void fetch_pipe_params(struct display_mode_lib *mode_lib)
 			for (k = j + 1; k < mode_lib->vba.cache_num_pipes; ++k) {
 				display_pipe_source_params_st *src_k = &pipes[k].pipe.src;
 				display_pipe_dest_params_st *dst_k = &pipes[k].pipe.dest;
-				display_output_params_st *dout_k = &pipes[j].dout;
 
 				if (src_k->is_hsplit && !visited[k]
 						&& src->hsplit_grp == src_k->hsplit_grp) {
@@ -620,8 +619,6 @@ static void fetch_pipe_params(struct display_mode_lib *mode_lib)
 						mode_lib->vba.ViewportHeightChroma[mode_lib->vba.NumberOfActivePlanes] +=
 								src_k->viewport_height_c;
 					}
-					mode_lib->vba.NumberOfDSCSlices[mode_lib->vba.NumberOfActivePlanes] +=
-							dout_k->dsc_slices;
 
 					visited[k] = true;
 				}