Merge "floss: use pkg-config for linking protobuf and flatbuffers" into main

    println!("cargo:rerun-if-changed={}", cxx_outdir.into_string().unwrap());

    // A few dynamic links

    println!("cargo:rustc-link-lib=dylib=flatbuffers");

    println!("cargo:rustc-link-lib=dylib=protobuf");

    Config::new().probe("flatbuffers").unwrap();

    Config::new().probe("protobuf").unwrap();

    println!("cargo:rustc-link-lib=dylib=resolv");

    // Clang requires -lc++ instead of -lstdc++