On my system the sysctl output looks like this:
dev.hwpstate_intel.0.epp: 50 dev.hwpstate_intel.0.%parent: cpu0 dev.hwpstate_intel.0.%pnpinfo: dev.hwpstate_intel.0.%location: dev.hwpstate_intel.0.%driver: hwpstate_intel dev.hwpstate_intel.0.%desc: Intel Speed Shift
but all the % get escaped in the manual page, I'm not sure if this is intended.
While here, move the example of dev.hwpstate_intel.%d.%parent after the
description to align with others.