reproduce (this is a W=1 build):
        git remote add android-common https://android.googlesource.com/kernel/common
        git fetch --no-tags android-common android14-kiwi-6.1
        git checkout 2ff3b23c7fde9ad4a23158d219b9e9a5a0e90982
        # apt-get install llvm-dev

        # save the config file
        make W=1 ARCH=x86_64 olddefconfig
        make W=1 ARCH=x86_64 
        make W=1 headers_install
        make W=1 -C tools/testing/selftests