cmd/compile: get rid of zero-sized values in call expansion

cmd/compile: get rid of zero-sized values in call expansion

Do this by removing all stores of zero-sized anything.

Fixes #63433.

Change-Id: I5d8271edab992d15d02005fa3fe31835f2eff8fa
Reviewed-on: https://go-review.googlesource.com/c/go/+/534296
Reviewed-by: Keith Randall <khr@golang.org>
Reviewed-by: Cuong Manh Le <cuong.manhle.vn@gmail.com>
Run-TryBot: David Chase <drchase@google.com>
Reviewed-by: Keith Randall <khr@google.com>
TryBot-Result: Gopher Robot <gobot@golang.org>