Fix (unused) extintr_disable_by_num behaviour, and make vmstat -i output provide the correct irq numbers.
Fix (unused) extintr_disable_by_num behaviour, and make vmstat -i output
provide the correct irq numbers.

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