Do --always-sparkplug compilations in a separate function, and
allow that function to return false if a sparkplug compilation
fails. Similarly, don't assert that --always-sparkplug requires
a function to have baseline code, in case a previous sparkplug
compilation failed.

Fixed: chromium:1185735, chromium:1185739
Change-Id: I363fcf271395afa2ec47228fff7a28a76c157f0f
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/2744735
Commit-Queue: Leszek Swirski <leszeks@chromium.org>
Commit-Queue: Toon Verwaest <verwaest@chromium.org>
Auto-Submit: Leszek Swirski <leszeks@chromium.org>
Reviewed-by: Toon Verwaest <verwaest@chromium.org>
Cr-Commit-Position: refs/heads/master@{#73292}