windows: regenerate zsyscall_windows.go

Change-Id: I714d13f534520a444dd9601d280d32c4427a8e69
GitHub-Last-Rev: 861daf25d8330bdc3c50ab94f2429d6eecba53a5
GitHub-Pull-Request: golang/sys#236
Reviewed-on: https://go-review.googlesource.com/c/sys/+/626379
Commit-Queue: Ian Lance Taylor <iant@google.com>
Reviewed-by: Alex Brainman <alex.brainman@gmail.com>
Reviewed-by: Ian Lance Taylor <iant@google.com>
Reviewed-by: Cherry Mui <cherryyz@google.com>
Auto-Submit: Ian Lance Taylor <iant@google.com>
LUCI-TryBot-Result: Go LUCI <golang-scoped@luci-project-accounts.iam.gserviceaccount.com>