clang-cl on Windows fails to compile after zlib-ng

[chris-eibl]

Since #131438, clang-cl fails to compile, see e.g. the tailcall Windows CI
https://github.com/python/cpython/actions/runs/13967899073/job/39102464260

Discussion started with @zooba in #131438 (comment).

Linked PRs

• GH-131521: fix clangcl build on Windows for zlib-ng #131526

[zooba]

The config files for zlib-ng require CMake to generate, which we don't use as part of our build, so they were generated once for MSVC and added under the PC directory.

These will probably need tweaking to support clang-cl.