In Find modules with native pkg-config detection (libgsasl, libidn2,
libssh, libuv, nettle) use the C compiler flags returned by pkg-config.
Also use the library paths, and return the pathless library names.
Also:
- add these library paths to `libcurl.pc`/`curl-config`.
- fix libgsasl detection to use the detected header directory.
FindGSS already did this before this patch.
Fixes#14641Closes#14652
For: libgsasl, libidn2, libssh, libuv.
The new Find modules retain using `pkg-config` natively, not as a "hint"
for the CMake-native detection. Of the pre-existing Find modules, only
FindNettle, and FindGSS (with customized code) work this way. Align
detection code for the new modules and add version detection for the
CMake-native paths.
Also, add CMake-native detection for `libgsasl`.
The remaining outlier in `CMakeLists.txt` is GnuTLS, which has
a CMake built-in Find module, but which lacks `pkg-config` support,
required for vcpkg. It remains unchanged.
Another part-outlier is `libssh`, which keeps requiring the trick
`find_package(libssh CONFIG QUIET)` for reasons I could not yet figure
out.
Closes#14555
