drop cmake/Findc-ares.cmake once distros package c-ares's CMake config files.

[tchaikov]

in order to reduce the load of maintenance, we should consider dropping cmake/Findc-ares.cmake if we can detect c-ares in config mode.

the c-ares-devel package in fedora 40+ includes the CMake config files:

$ rpm -ql c-ares-devel | grep cmake
/usr/lib64/cmake/c-ares
/usr/lib64/cmake/c-ares/c-ares-config-version.cmake
/usr/lib64/cmake/c-ares/c-ares-config.cmake
/usr/lib64/cmake/c-ares/c-ares-targets-noconfig.cmake
/usr/lib64/cmake/c-ares/c-ares-targets.cmake

but unfortunately, the latest debian stable release (bookworm) still does not package them, see https://debian.pkgs.org/12/debian-main-amd64/libc-ares-dev_1.18.1-3_amd64.deb.html . debian sid does, see https://debian.pkgs.org/sid/debian-main-amd64/libc-ares-dev_1.33.1-2_amd64.deb.html .

we can reevaluate the situation once debian creates a new release (13).

[bradh352]

@gjasny I guess this is the right ticket about missing cmake files in the debian packaging.

[bradh352]

not sure if debian would backport a change to include those files into stable, I see where its mentioned debian sid apparently corrects this issue.

[gjasny]

The old stable releases used the autotools build system which did not generate the CMake config file. I don’t think that adding the file in stable would be possible.

[p12tic]

I think it makes sense to consider waiting at least a year after Debian 13 is released.