runtime: support register ABI Go functions from Windows callbacks

This change modifies the system that allows Go functions to be set as
callbacks in various Windows systems to support the new register ABI.

For #40724.

Change-Id: Ie067f9e8a76c96d56177d7aa88f89cbe7223e12e
Reviewed-on: https://go-review.googlesource.com/c/go/+/300113


Reviewed-by: Austin Clements <austin@google.com>
Reviewed-by: Cherry Zhang <cherryyz@google.com>
Trust: Michael Knyszek <mknyszek@google.com>
Run-TryBot: Michael Knyszek <mknyszek@google.com>
TryBot-Result: Go Bot <gobot@golang.org>