.. into new virtual subclass TurbofanCompilationJob. Update all TF code
to derive from this class. Specifically, the OptimizedCompilationInfo is
TF-specific and now lives in TurbofanCompilationJob.

The motivation behind this is that Maglev now also uses this
infrastructure.

Drive-by: Replace CompilationMode with ConcurrencyMode.

Bug: v8:7700
Change-Id: Iae6d1ffd1c810e2e45cad6c9b4e43d4c82ac54a7
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/3528493Reviewed-by: Tobias Tebbi <tebbi@chromium.org>
Auto-Submit: Jakob Gruber <jgruber@chromium.org>
Reviewed-by: Jakob Kummerow <jkummerow@chromium.org>
Commit-Queue: Jakob Kummerow <jkummerow@chromium.org>
Cr-Commit-Position: refs/heads/main@{#79515}