acpicpu(4) on OpenBSD

The text 71db57e170e1, as OpenBSD 7.2, OpenBSD 7.1, OpenBSD 7.0, OpenBSD 6.9, OpenBSD 6.8, OpenBSD 6.7, OpenBSD 6.6, OpenBSD 6.5, OpenBSD 6.4, OpenBSD 6.3 shipped it.

ACPI processor power and performance state