The ProfileEntryHookStub is no longer used and can be removed.

Bug: v8:7777, v8:8503
Change-Id: I4ccd75d38cfee3e7963338d5d8213915db9be4a9
Reviewed-on: https://chromium-review.googlesource.com/c/1349191
Commit-Queue: Jakob Gruber <jgruber@chromium.org>
Reviewed-by: Michael Starzinger <mstarzinger@chromium.org>
Reviewed-by: Yang Guo <yangguo@chromium.org>
Reviewed-by: Jakob Kummerow <jkummerow@chromium.org>
Cr-Commit-Position: refs/heads/master@{#57823}