We add a map from condition nodes to respective BranchConditions in
ControlPathConditions for faster lookup.

Bug: v8:11510
Change-Id: I571514beb699b76f2a1a0245c4785f518b9d8b1b
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/3041676
Commit-Queue: Manos Koukoutos <manoskouk@chromium.org>
Reviewed-by: Georg Neis <neis@chromium.org>
Cr-Commit-Position: refs/heads/master@{#76232}