reproduce (this is a W=1 build):
        git clone https://github.com/intel/lkp-tests.git ~/lkp-tests
        # https://github.com/esmil/linux/commit/a731cec45ec032408be9a21ab8e1ecc5a1f33ce1
        git remote add esmil https://github.com/esmil/linux
        git fetch --no-tags esmil th1520
        git checkout a731cec45ec032408be9a21ab8e1ecc5a1f33ce1
        # save the config file
        mkdir build_dir && cp config build_dir/.config
        ~/lkp-tests/kbuild/make.cross W=1 O=build_dir ARCH=hexagon olddefconfig
        ~/lkp-tests/kbuild/make.cross W=1 O=build_dir ARCH=hexagon SHELL=/bin/bash drivers/pinctrl/