MinorMC maintained a separate marking state to support interleaved GCs.
Since MinorMC now assumes that interleaving is not possible, MinorMC can
use the same marking state as the full GC.

Bug: v8:12612
Change-Id: Ibeb7df2eb24e448f811b497c9d16b3b132f87ec2
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/3735163Reviewed-by: Michael Lippautz <mlippautz@chromium.org>
Commit-Queue: Omer Katz <omerkatz@chromium.org>
Cr-Commit-Position: refs/heads/main@{#81468}