Portable Windows builds
MikeDuk requested portable Windows builds in https://forum.freeciv.org/f/viewtopic.php?t=93557
The same patch applies to main and S3_2, just use -p2 on S3_2 to skip "platforms" as a path component.
MikeDuk requested portable Windows builds in https://forum.freeciv.org/f/viewtopic.php?t=93557