os: mark Solaris nam/door/port files as irregular

os: mark Solaris nam/door/port files as irregular

No test because I'm too lazy to figure out how to create such files.

Fixes #52259

Change-Id: I7a07f49993cf046888729e9206ed53dddcf9cb13
Reviewed-on: https://go-review.googlesource.com/c/go/+/399435
Run-TryBot: Ian Lance Taylor <iant@golang.org>
Reviewed-by: Emmanuel Odeke <emmanuel@orijtech.com>
Reviewed-by: Ian Lance Taylor <iant@google.com>
Auto-Submit: Ian Lance Taylor <iant@google.com>
TryBot-Result: Gopher Robot <gobot@golang.org>
Reviewed-by: Russ Cox <rsc@golang.org>