[wasm][fuzzer] Fuzz Liftoff debug code paths

Add a flag similar to the tiering mask to choose between regular
baseline code or debug code in Liftoff.

R=clemensb@chromium.org

Bug: chromium:1183774
Change-Id: I0e87154e2e1cd57679ce0c57bb1e075a97691248
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/2807603


Reviewed-by: Clemens Backes <clemensb@chromium.org>
Commit-Queue: Thibaud Michaud <thibaudm@chromium.org>
Cr-Commit-Position: refs/heads/master@{#73833}