Merge pull request #2630 from verilog-to-routing/rr_graph_edge_bug

RR graph edge creation uses a incorrect switch type for decremental tracks

Author: vaughnbetz

vpr/src/route/rr_graph2.cpp

@@ -836,7 +836,7 @@ int get_unidir_opin_connections(RRGraphBuilder& rr_graph_builder,
         rr_edges_to_create.emplace_back(from_rr_node, inc_inode_index, to_switch, false);
         ++num_edges;
 
-        to_switch = (opin_layer == track_layer) ? seg_details[inc_track].arch_opin_switch() : seg_details[dec_track].arch_opin_between_dice_switch();
+        to_switch = (opin_layer == track_layer) ? seg_details[dec_track].arch_opin_switch() : seg_details[dec_track].arch_opin_between_dice_switch();
         rr_edges_to_create.emplace_back(from_rr_node, dec_inode_index, to_switch, false);
         ++num_edges;
     }