build-gettext: Don't build emacs bindings. * src/build-gettext.mk: The `emacs` installed on the build system might be incompatible with the STL built by build-gcc. We probably don't need the emacs bindings for the `gettext` build tool anyway. So skip building those bindings.

#include <google/protobuf/stubs/common.h>

int
main()
{
    GOOGLE_PROTOBUF_VERIFY_VERSION;
    google::protobuf::ShutdownProtobufLibrary();
    return 0;
}