CMake: Replace deprecated protobuf_generate_cpp()

[Nordup]

I was getting an error when building (manjaro with cmake 3.28.1):
Unknown CMake command "protobuf_generate_cpp"

Found a solution here: https://stackoverflow.com/a/56896032/13580789

Udp: switched to protobuf_generate() as discussed

[Krzmbrzl]

Relevant: https://gitlab.kitware.com/cmake/cmake/-/issues/21228

It seems like there should be a "cleaner" way of solving this but this probably involves digging around Protobuf and cmake sources and checking whether the respective behaviors are version-dependent. So I guess this simple fix will do.

@davidebeatrici opinion?

[davidebeatrici]

We should switch to protobuf_generate(): https://cmake.org/cmake/help/latest/module/FindProtobuf.html#command:protobuf_generate

[Krzmbrzl]

See also https://chromium.googlesource.com/external/github.com/protocolbuffers/protobuf/+/refs/heads/main-202303072257/docs/cmake_protobuf_generate.md

[Nordup]

I'm closing this PR then?

[davidebeatrici]

Well, it works as a workaround but it would be great to switch directly to the new function.

[Nordup]

Will this do? :)

[Nordup]

Why downloading on windows is failing((
error: https://repo.msys2.org/mingw/i686/mingw-w64-i686-libwinpthread-git-9.0.0.6373.5be8fcd83-1-any.pkg.tar.zst: failed: status code 404

[davidebeatrici]

Sorry for the delay, see microsoft/vcpkg#36502.

We can ignore the failure for the time being, as I can test the PR on Windows myself.

[davidebeatrici]

Fixed in #22.

[davidebeatrici]

Thank you very much for your contribution!

[Nordup]

It’s a pleasure 😇