3.13.0-156.206) is not available, but a newer one is (3.13.0-166.216). We redirected you there.
/usr/lib/linux-tools/4.4.0-134-lowlatency/cpupower is in linux-tools-4.4.0-134-lowlatency 4.4.0-134.160.
This file is owned by root:root, with mode 0o777.
It is a symlink to /usr/lib/linux-tools/4.4.0-134-lowlatency/../../linux-tools-4.4.0-134/cpupower