This PR adds to https://github.com/microsoft/vcpkg/pull/31889 by also
removing the MSVC `/WX` flag, to disable "Treat all compiler warnings as
errors" for MSVC too.
- [x] Changes comply with the [maintainer
guide](https://github.com/microsoft/vcpkg-docs/blob/main/vcpkg/contributing/maintainer-guide.md).
- [ ] SHA512s are updated for each updated download.
- [ ] The "supports" clause reflects platforms that may be fixed by this
new version.
- [ ] Any fixed [CI
baseline](https://github.com/microsoft/vcpkg/blob/master/scripts/ci.baseline.txt)
entries are removed from that file.
- [ ] Any patches that are no longer applied are deleted from the port's
directory.
- [x] The version database is fixed by rerunning `./vcpkg x-add-version
--all` and committing the result.
- [x] Only one version is added to each modified port's versions file.
