[bug fix] analytical place with graphics no longer segfault#3273

AlexandreSinger merged 2 commits intoverilog-to-routing:masterverilog-to-routing/vtr-verilog-to-routing:masterfrom

robluo:fix-ap-graphics-segfaultrobluo/vtr-verilog-to-routing:fix-ap-graphics-segfaultCopy head branch name to clipboard