Make the "machine xir" ddb command work on machines with uperf(4) on sbus(4).
Make the "machine xir" ddb command work on machines with uperf(4) on sbus(4).

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