/usr/lib/linux-tools/4.15.0-1021-kvm/cpupower is in linux-tools-4.15.0-1021-kvm 4.15.0-1021.21.
This file is owned by root:root, with mode 0o777.
It is a symlink to /usr/lib/linux-tools/4.15.0-1021-kvm/../../linux-kvm-tools-4.15.0-1021/cpupower