Mark translations of manuals with %lang()
    
    Minimal environments, like container images built for deploying
    applications, may not want to install localization files.  eg., the
    fedora base image sets the %_install_langs RPM macro to en_US in
    /etc/rpm/macros.image-language-conf.
    
    This requires localization files to be marked with %lang().  Otherwise,
    they will still get installed regardless of %_install_langs.
    
    https://src.fedoraproject.org/rpms/xz/pull-request/10