...to honor the {pinned} list under all circumstances.

Drive-by: DEBUG-mode helpers to print FunctionSig and LiftoffRegList
objects to stdout.

Fixed: chromium:1356718
Change-Id: I487db12294f687790cec1d658d7a7d754f3c2f99
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/3859752Reviewed-by: Clemens Backes <clemensb@chromium.org>
Auto-Submit: Jakob Kummerow <jkummerow@chromium.org>
Commit-Queue: Jakob Kummerow <jkummerow@chromium.org>
Cr-Commit-Position: refs/heads/main@{#82815}