Came across this cast while checking a CFI issue. It reinterpret_casts
between two identical function pointers, so it is redundant.

R=ulan@chromium.org

Bug: v8:7570
Change-Id: I2d92e93788027e41abdb12af8371251c0da6a709
Reviewed-on: https://chromium-review.googlesource.com/1004674Reviewed-by: Ulan Degenbaev <ulan@chromium.org>
Commit-Queue: Clemens Hammacher <clemensh@chromium.org>
Cr-Commit-Position: refs/heads/master@{#52507}