The allowlist used for `Deoptimizer::IsValidReturnAddress` depends on
fixed embedded builtin addresses. Pass a pointer to the isolate to
this method, so that it can discover the actual builtin code start
(which may have been remapped) and calculate the offset from the start
of the builtins' code in order to check if the return address is
allowed.

After this change, do not disable short builtin calls when CFI is
enabled.

There's an important TODO for this change:
Since the builtin code pointer that's used to check whether a return
address is allowed is now writable, we should use pointer authentication
to protect it.

Bug: v8:10026
Change-Id: Iafd31d3ad7e10cb17faf33e76e78d3df36edeefd
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/3667506Reviewed-by: Toon Verwaest <verwaest@chromium.org>
Reviewed-by: Igor Sheludko <ishell@chromium.org>
Commit-Queue: Georgia Kouveli <georgia.kouveli@arm.com>
Cr-Commit-Position: refs/heads/main@{#81049}