[dev.typeparams] runtime/internal/sys: replace ArchFamily and constants with goarch

[dev.typeparams] runtime/internal/sys: replace ArchFamily and constants with goarch

Refactoring with rf

    rf 'ex . {
      import "internal/goarch"
      import "runtime/internal/sys"
      sys.ArchFamily -> goarch.ArchFamily
      sys.AMD64 -> goarch.AMD64
      sys.ARM -> goarch.ARM
      sys.ARM64 -> goarch.ARM64
      sys.I386 -> goarch.I386
      sys.MIPS -> goarch.MIPS
      sys.MIPS64 -> goarch.MIPS64
      sys.PPC64 -> goarch.PPC64
      sys.RISCV64 -> goarch.RISCV64
      sys.S390X -> goarch.S390X
      sys.WASM -> goarch.WASM
    }'

Change-Id: I0cc29ed3fdcf9ff39aa901d8bc92270996f0821c
Reviewed-on: https://go-review.googlesource.com/c/go/+/328341
Trust: Michael Knyszek <mknyszek@google.com>
Run-TryBot: Michael Knyszek <mknyszek@google.com>
TryBot-Result: Go Bot <gobot@golang.org>
Reviewed-by: Matthew Dempsky <mdempsky@google.com>