[vcpkg_fixup_pkgconfig] HOTFIX -- revert #19469

[ras0219]

PR #19469 regressed pkgconfig for libcurl. This was not detected because it also regressed the self-check mechanism (removed argument from vcpkg_fixup_pkgconfig_check_files without removing the argument from the callers).

Because there are a large number of changes in the helper and the internal consistency check was disabled, I'm reverting the entire change so it can go through a proper separate PR process again.

Fixes #19606

[ras0219-msft]

Bypassing full CI check because this is a revert back to a known good state. I've manually reviewed the changes in #19469 to ensure that this file can be independently rolled back.

[dg0yt]

Thanks for the quick fix.
For the record, port gdal heavily depends on pkgconfig files, and I intentionally added configuration verification to the portfile because I thought this could be fragile. Now on the first true positive alert from the gdal alert bells, it was ignored although the CI logs provided clear hints. 😞