cmd/compile: add edge from lock rank edge from forceGC to traceStackTab

This edge can happen when forcegchelper() calls
goparkunlock(&forcegc.lock, ...) while holding the forcegc lock.
goparkunlock() eventually calls park_m(). In park_m(), traceGoPark()
(which leads to (*traceStackTable).put() and acquires the traceStackTab
lock) can be called before the forcegc lock is released.

Fixes #45774

Change-Id: If0fceab596712eb9ec0b9b47326778bc0ff80913
Reviewed-on: https://go-review.googlesource.com/c/go/+/316029


Run-TryBot: Dan Scales <danscales@google.com>
TryBot-Result: Go Bot <gobot@golang.org>
Reviewed-by: Michael Knyszek <mknyszek@google.com>
Trust: Carlos Amedee <carlos@golang.org>