cmd/go: use -buildmode=pie as default on window

This change adjusts go command to pass -buildmode=pie to cmd/link,
if -buildmode is not explicitly provided.

Fixes #35192

Change-Id: Iec020131e676eb3e9a2df9eea1929b2af2b6df04
Reviewed-on: https://go-review.googlesource.com/c/go/+/230217


Run-TryBot: Alex Brainman <alex.brainman@gmail.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Ian Lance Taylor <iant@golang.org>