In the runtime, we always had a convention to use int-typed accessors
for Smi fields. For Torque-generated classes, we kept them Smi-typed
but then added int wrappers around that.
This CL makes Torque generate int-typed accessors directly, removing the
need for these wrappers.

TBR=hpayer@chromium.org

Bug: v8:7793
Change-Id: I348e1d96295c9676fafda32b7d49088848527f89
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/2106210
Commit-Queue: Tobias Tebbi <tebbi@chromium.org>
Reviewed-by: Nico Hartmann <nicohartmann@chromium.org>
Cr-Commit-Position: refs/heads/master@{#66760}