reproduce (this is a W=1 build):
        # https://github.com/jpirko/linux_mlxsw/commit/ece314cf9fe4375f3bd05b6b47cc8e771da18322
        git remote add jpirko-mlxsw https://github.com/jpirko/linux_mlxsw
        git fetch --no-tags jpirko-mlxsw combined_queue
        git checkout ece314cf9fe4375f3bd05b6b47cc8e771da18322

        # save the config file
        mkdir build_dir && cp config build_dir/.config
        make W=1 O=build_dir ARCH=x86_64 olddefconfig
        make W=1 O=build_dir ARCH=x86_64 SHELL=/bin/bash