[cygwin]. Add cygwin.exe along with msys2.exe that comes with MSYSTEM=CYGWIN

[lygstate]

As in future MSYSTEM=CYGWIN will be default? I think

[lazka]

Certainly a possibility, though how "cygwin" would this "cygwin" be, i.e. which MSYS2 changes are left out.

[lygstate]

Certainly a possibility, though how "cygwin" would this "cygwin" be, i.e. which MSYS2 changes are left out.

How about create a new packages called CYGWIN-packages, that at the start point of MSYS2-packages, and all the cyg->msys- are dropped.

Then merge MINGW-packages into CYGWIN-packages, currently the packages are at the top directory, we can place all packages in ports directory or packages directory.

The arch=('any') is keeped, once not any, then it's a explicit list of arch that can be built.
That's the subset of ('mingw64' 'ucrt64' 'clang64' 'clangarm64', 'cygwin')