reproduce:
        # https://github.com/bvanassche/linux/commit/01b5e165f509f2b8b0a4c7c78f613042e694e845
        git remote add bvanassche https://github.com/bvanassche/linux
        git fetch --no-tags bvanassche scsi-remove-slave-configure
        git checkout 01b5e165f509f2b8b0a4c7c78f613042e694e845
        make menuconfig
        # enable CONFIG_COMPILE_TEST, CONFIG_WARN_MISSING_DOCUMENTS, CONFIG_WARN_ABI_ERRORS
        # install Sphinx 2.4.4
        make htmldocs