reproduce:
        git remote add brgl https://git.kernel.org/pub/scm/linux/kernel/git/brgl/linux.git
        git fetch brgl gpio/for-next
        git checkout brgl/gpio/for-next
        b4 shazam https://lore.kernel.org/r/20250701225355.2977294-1-robh@kernel.org
        make menuconfig
        # enable CONFIG_COMPILE_TEST, CONFIG_WARN_MISSING_DOCUMENTS, CONFIG_WARN_ABI_ERRORS
        # install Sphinx 3.4.3
        make htmldocs