Since upd(4) currently supports a known but limited number of sensors, parse the HID descriptor multiple times to find them.
Since upd(4) currently supports a known but limited number of sensors,
parse the HID descriptor multiple times to find them.

This logic is necessary to later create a tree of sensors in order to
avoid lookups in the hot path for sensors that depend on the value of
others.

From David Higgs.

orumin/openbsd-efivars,orumin/openbsd-efivars,orumin/openbsd-efivars,orumin/openbsd-efivars