runtime: use canonical wireguard-go repo for procyield() linkname usage
The source code quoted tailscale's development fork, which is only a
development fork. The canonical github url is actually
github.com/wireguard/wireguard-go, but that's really just a mirror of
git.zx2c4.com/wireguard-go, and in any case, the proper go package name
is golang.zx2c4.com/wireguard, so just use that.
Change-Id: Ifa63c1c538989b3fcebcf06d1c238469bc73724d
Reviewed-on: https://go-review.googlesource.com/c/go/+/616736
Auto-Submit: Jason Donenfeld <Jason@zx2c4.com>
LUCI-TryBot-Result: Go LUCI <golang-scoped@luci-project-accounts.iam.gserviceaccount.com> Reviewed-by: Michael Knyszek <mknyszek@google.com> Reviewed-by: Ian Lance Taylor <iant@google.com>