cmd/go: simplify code thanks to reflect.Value.SetZero
Change-Id: Ie9c05210390dae43faf566907839bce953925735
Reviewed-on: https://go-review.googlesource.com/c/go/+/471258
TryBot-Result: Gopher Robot <gobot@golang.org>
Run-TryBot: Ian Lance Taylor <iant@golang.org> Reviewed-by: Than McIntosh <thanm@google.com> Reviewed-by: Ian Lance Taylor <iant@google.com> Reviewed-by: Joseph Tsai <joetsai@digital-static.net>
Run-TryBot: Daniel Martí <mvdan@mvdan.cc>