This reverts commit 2338a2fd.

Reason for revert: broke mips

see https://ci.chromium.org/buildbot/client.v8.ports/V8%20Mips%20-%20builder/17573

Original change's description:
> [wasm] Add simd mem and shift ops to interpreter
> 
> R=​clemensh@chromium.org
> BUG=v8:6020
> 
> Change-Id: I5d95e4c23240ae4e174d896d31e1b9b1d89d9418
> Reviewed-on: https://chromium-review.googlesource.com/1096493
> Reviewed-by: Clemens Hammacher <clemensh@chromium.org>
> Commit-Queue: Aseem Garg <aseemgarg@chromium.org>
> Cr-Commit-Position: refs/heads/master@{#53717}

TBR=aseemgarg@chromium.org,clemensh@chromium.org

Change-Id: I8e5b2e9a9c1c09d035335ba6681bbe3e1ce5abfb
No-Presubmit: true
No-Tree-Checks: true
No-Try: true
Bug: v8:6020
Reviewed-on: https://chromium-review.googlesource.com/1099776Reviewed-by: Sathya Gunasekaran <gsathya@chromium.org>
Commit-Queue: Sathya Gunasekaran <gsathya@chromium.org>
Cr-Commit-Position: refs/heads/master@{#53718}