Changes:
- Add possibility to define and emit all reference types.
- Simplify function locals definition.
- Change 'type' to 'type_index' where appropiate.

Bug: v8:7748
Change-Id: Ie35a6204369e678298ee2ff2ec7c7793c5315c3e
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/2390144
Commit-Queue: Manos Koukoutos <manoskouk@chromium.org>
Reviewed-by: Thibaud Michaud <thibaudm@chromium.org>
Cr-Commit-Position: refs/heads/master@{#69814}