cad/openroad: Fix build with swig 4.2.1 and tcl 8.6
/wrkdirs/usr/ports/cad/openroad/work/.build/src/gui/tclSwig.h:1623:11: error: unknown type name 'Tcl_Size'; did you mean 'Tcl_Time'?
Reference: https://github.com/swig/swig/commit/b91ffa5631eb049293d3478744606148c9726521