Forbid using LoadRoot in CSA (with a bailout via CodeAssembler), so that
users are forced to use helper macros for roots, which have statically
known types. Convert all current uses of LoadRoot to use these macros,
introducing new ones where necessary.

Bug: v8:9396
Change-Id: I91214fca6e5ace7554d79605706a8a60117468fa
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/1762526
Commit-Queue: Leszek Swirski <leszeks@chromium.org>
Reviewed-by: Tobias Tebbi <tebbi@chromium.org>
Reviewed-by: Igor Sheludko <ishell@chromium.org>
Cr-Commit-Position: refs/heads/master@{#63398}