runtime: convert windows/arm64 assembly

The assembly is mostly a straightforward conversion of the
equivalent arm assembly.

This CL is part of a stack adding windows/arm64
support (#36439), intended to land in the Go 1.17 cycle.

Change-Id: I61b15d712ade4d3a7285c7680de8e0987aacba10
Reviewed-on: https://go-review.googlesource.com/c/go/+/288828


Trust: Russ Cox <rsc@golang.org>
Trust: Jason A. Donenfeld <Jason@zx2c4.com>
Reviewed-by: Cherry Zhang <cherryyz@google.com>