cmd: delete some more windows/arm remnants

cmd: delete some more windows/arm remnants

Updates #71671

Amends CL 699176, CL 698415, CL 698036, CL 648795.

Change-Id: I69adff73d1c9631e07df63fc84c80ec0204d49d5
Reviewed-on: https://go-review.googlesource.com/c/go/+/700835
Reviewed-by: Michael Pratt <mpratt@google.com>
LUCI-TryBot-Result: Go LUCI <golang-scoped@luci-project-accounts.iam.gserviceaccount.com>
Reviewed-by: Dmitri Shuralyov <dmitshur@google.com>
Reviewed-by: Dmitri Shuralyov <dmitshur@golang.org>