MinGW32 is getting long in the tooth and is missing a lot of modern
Windows features as well as having broken headers.  Most people will
be using MinGW-w64 at this point, so add support for it.  Once I
ensure SyncTERM works properly with it, MinGW32 support will be
discontinued.

I suspect this will impact exactly zero people since the reason this
exists is to build the Win32 versions of SyncTERM on FreeBSD.

Changes:
- Explicitly request 32-bit Windows output
- Detect the string "mingw32" anywhere in the hardware description
- Explicitly link with libuuid
- Add a terrible hack to syncterm.c to block wincrypt.h