os: trivial comment fix
"Geese" here looks like an autocorrect-o of "oses", I think writing it out
makes more sense.
Change-Id: Iba89a6c0b94657e2e93937cc153f07aea1d04e04
GitHub-Last-Rev:
4f3a780f327d6c807e9b154d781ee69a10d391e4
GitHub-Pull-Request: golang/go#74332
Reviewed-on: https://go-review.googlesource.com/c/go/+/682776
LUCI-TryBot-Result: Go LUCI <golang-scoped@luci-project-accounts.iam.gserviceaccount.com>
Reviewed-by: Keith Randall <khr@golang.org>
Auto-Submit: Keith Randall <khr@golang.org>
Reviewed-by: Keith Randall <khr@google.com>
Reviewed-by: Dmitri Shuralyov <dmitshur@google.com>