This flag disables the implicit fallback to Turbofan when
Liftoff bails out due to an unsupported instruction/type.
Instead, Liftoff bailouts are treated as fatal errors.

This is meant for testing; it is not (yet?) a configuration
we support in production.

Change-Id: I04e2045f1976e202e65da0ba8e8d660c47859bf4
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/2584949Reviewed-by: Andreas Haas <ahaas@chromium.org>
Commit-Queue: Andreas Haas <ahaas@chromium.org>
Auto-Submit: Jakob Kummerow <jkummerow@chromium.org>
Cr-Commit-Position: refs/heads/master@{#71721}