Log Message:
cad/libredwg: Update to 0.12.4

Major bugfixes:
  * Fixed encode from dwg and json for many objects: missing size and bitsize
    recalculation for objects with strings and DD types. (GH #322, #326)
  * dwgadd: Fixed the pspace command. (GH #319)
  * Missed all binary DXF groups 0. Still not working, but added to oss-fuzz.
  * Support older gperf, older than 3.1. eg. macOS