Windows: Disable MinGW64 linker feature that spuriously fails.
Windows: Disable MinGW64 linker feature that spuriously fails.

* This fails for some files and is considered experimental, so disable
  it on older MinGW64 versions.

* The CondaCC seems affected at least, so maybe gcc 6 was OK, can still
  bump it up if other people report otherwise.

kayhayen/Nuitka,kayhayen/Nuitka,kayhayen/Nuitka,kayhayen/Nuitka