syscall: rm go:linkname from origRlimitNofile

syscall: rm go:linkname from origRlimitNofile

Since CL 588076 runc can do fine without the kludge. The code accessing the symbol is now guarded with `go:build !go1.23` in all supported runc branches (main: [1], release-1.1: [2]).

This reverts part of CL 587219.

Updates #67401.

For #66797.

[1]: https://github.com/opencontainers/runc/pull/4290
[2]: https://github.com/opencontainers/runc/pull/4299

Change-Id: I204843a93c36857e21ab9b43bd7aaf046e8b9787
Reviewed-on: https://go-review.googlesource.com/c/go/+/587918
Auto-Submit: Ian Lance Taylor <iant@google.com>
Reviewed-by: Michael Knyszek <mknyszek@google.com>
Reviewed-by: Ian Lance Taylor <iant@google.com>
LUCI-TryBot-Result: Go LUCI <golang-scoped@luci-project-accounts.iam.gserviceaccount.com>