libffi-rs with msvc win11x64, mingw, and wsl ubuntu

[davehorner]

I have a system that includes msys2 and wsl. I was having trouble and still am having trouble in wsl linux. My focus was on a msvc build and I found a work around.

I was attempting to get this project to build.
svix/svix-webhooks#1128

fatal error C1083: Cannot open include file: 'fficonfig.h': No such file or **directory**

The windows build was erroring with a missing header file. The ubuntu build is failing without any real detail and I'm not sure how to debug or resolve that.

I was able to get the windows build working using the following before doing a cargo build:

set INCLUDE=%INCLUDE%;libffi\include;libffi-sys-2.3.0\libffi\src\x86\

I hope this helps someone else if they encounter the windows build issue. I'd really like to help resolve the issue without a work around. Please have a look at the associated ticket and let me know if there is anything I can test or help with further.

thanks.