When allocating a buffer, use the supplied length if the requested length is smaller. Tested by joris@, ok gwk@
When allocating a buffer, use the supplied length if the requested
length is smaller. Tested by joris@, ok gwk@

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