all: delete remaining windows/arm code

all: delete remaining windows/arm code

Fixes #43800
Updates #71671

Change-Id: Ib7aafe3a3f6ae48f23fa23f03103820e9fcf5161
Reviewed-on: https://go-review.googlesource.com/c/go/+/698415
Reviewed-by: Quim Muntal <quimmuntal@gmail.com>
Reviewed-by: Cherry Mui <cherryyz@google.com>
LUCI-TryBot-Result: Go LUCI <golang-scoped@luci-project-accounts.iam.gserviceaccount.com>
Reviewed-by: Dmitri Shuralyov <dmitshur@google.com>
Reviewed-by: Filippo Valsorda <filippo@golang.org>