syscall: add Setuid for aix
Fixes #67651
Change-Id: I8128433ddd040c8b91d7b6264200e19433d7a7dc
GitHub-Last-Rev:
7557a88cf5a52a99e7689b604964cd4ec8e6bfec
GitHub-Pull-Request: golang/go#67656
Reviewed-on: https://go-review.googlesource.com/c/go/+/588119
Reviewed-by: Than McIntosh <thanm@google.com>
LUCI-TryBot-Result: Go LUCI <golang-scoped@luci-project-accounts.iam.gserviceaccount.com>
Run-TryBot: Mauri de Souza Meneguzzo <mauri870@gmail.com>
TryBot-Bypass: Ian Lance Taylor <iant@golang.org>
Auto-Submit: Ian Lance Taylor <iant@google.com>
Reviewed-by: Ian Lance Taylor <iant@google.com>