This adds a {wasm::DebugInfo} struct which will hold the
{wasm::DebugSideTable}s for individual Liftoff functions, and will use
them to construct local scope information.

R=jkummerow@chromium.org, bmeurer@chromium.org

Bug: v8:10019
Change-Id: I7869cec5000e9b126c891a242fcccfc53c67662e
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/1975758
Commit-Queue: Clemens Backes <clemensb@chromium.org>
Reviewed-by: Jakob Kummerow <jkummerow@chromium.org>
Reviewed-by: Benedikt Meurer <bmeurer@chromium.org>
Cr-Commit-Position: refs/heads/master@{#65563}