[release-branch.go1.22] cmd/compile: put constants before variables in initialization...

[release-branch.go1.22] cmd/compile: put constants before variables in initialization order

Fixes #67820.

Change-Id: I03f4d4577b88ad0a92b260b2efd0cb9fe5082b2f
Reviewed-on: https://go-review.googlesource.com/c/go/+/575075
Reviewed-by: Robert Griesemer <gri@google.com>
Reviewed-by: Keith Randall <khr@google.com>
LUCI-TryBot-Result: Go LUCI <golang-scoped@luci-project-accounts.iam.gserviceaccount.com>
Reviewed-on: https://go-review.googlesource.com/c/go/+/590395
Reviewed-by: Michael Knyszek <mknyszek@google.com>
Reviewed-by: Keith Randall <khr@golang.org>