runtime: drop NetBSD kernel bug sysmon workaround fixed in NetBSD 9.2
The NetBSD releases supported by the NetBSD project as off today are 9.4
and 10.1. The Go project's NetBSD builders are on 9.3. Thus, it is fine
to drop the workaround which was only needed for NetBSD before 9.2.
Fixes #46495
Cq-Include-Trybots: luci.golang.try:gotip-netbsd-arm64
Change-Id: I3c2ec42fb0f08f7dafdfb7f1dbd97853afc16386
Reviewed-on: https://go-review.googlesource.com/c/go/+/687735
Auto-Submit: Tobias Klauser <tobias.klauser@gmail.com>
Auto-Submit: Benny Siegert <bsiegert@gmail.com> Reviewed-by: Benny Siegert <bsiegert@gmail.com> Reviewed-by: Michael Pratt <mpratt@google.com> Reviewed-by: Cherry Mui <cherryyz@google.com>
LUCI-TryBot-Result: Go LUCI <golang-scoped@luci-project-accounts.iam.gserviceaccount.com>