This reverts commit 1a69d8d8.

Reason for revert: Fails on nosse: https://ci.chromium.org/ui/p/v8/builders/ci/V8%20Linux/41365/overview

Original change's description:
> [wasm-simd] Fix i32x4.extadd_pairwise_i16x8_u codegen
>
> It did not handle the case where dst == src. We switch the registers
> used around to write to scratch first and ensure we don't overwrite dst.
>
> Bug: chromium:1187831
> Change-Id: Idf447aa1a3eff3920f2dfa3e0ec11efae37778cd
> Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/2762425
> Reviewed-by: Deepti Gandluri <gdeepti@chromium.org>
> Commit-Queue: Zhi An Ng <zhin@chromium.org>
> Cr-Commit-Position: refs/heads/master@{#73521}

Bug: chromium:1187831
Change-Id: I40d360b16338ef52e7e4327d4166c194ee950827
No-Presubmit: true
No-Tree-Checks: true
No-Try: true
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/2773802
Auto-Submit: Clemens Backes <clemensb@chromium.org>
Commit-Queue: Rubber Stamper <rubber-stamper@appspot.gserviceaccount.com>
Bot-Commit: Rubber Stamper <rubber-stamper@appspot.gserviceaccount.com>
Cr-Commit-Position: refs/heads/master@{#73522}