Since https://crrev.com/2951473002, there is only one reloc info for
code targets, so there is no need for the special {kCodeTargetMask}.

R=mstarzinger@chromium.org

Bug: v8:7754
Change-Id: I1055108c0128c7de0f5cfefc5e90bbd9dc75522a
Reviewed-on: https://chromium-review.googlesource.com/1098663Reviewed-by: Jakob Gruber <jgruber@chromium.org>
Reviewed-by: Michael Starzinger <mstarzinger@chromium.org>
Commit-Queue: Clemens Hammacher <clemensh@chromium.org>
Cr-Commit-Position: refs/heads/master@{#53776}