This adds sys/unix support for zos/s390x.
These changes should not affect other platforms.
Fixesgolang/go#43230
Change-Id: If1c1d9df134fbc44f95ca1b214e836508696da93
Reviewed-on: https://go-review.googlesource.com/c/sys/+/275992
Trust: Emmanuel Odeke <emmanuel@orijtech.com>
Trust: Tobias Klauser <tobias.klauser@gmail.com>
Run-TryBot: Emmanuel Odeke <emmanuel@orijtech.com>
Reviewed-by: Tobias Klauser <tobias.klauser@gmail.com>
Reviewed-by: Ian Lance Taylor <iant@golang.org>
billofarrell