This relands commit 009993ad.

The fix is in liftoff-assembler-ia32.h, the codegen was incorrect.

Original change's description:
> Implement f32x4.splat and enable handling this in Liftoff.
>
> We add a new macro for defining test cases to run on TurboFan, Liftoff,
> interpreter, and scalar lowering.
>
> Also add an assertion that the execution tier used is what we expected
> it to be. This is useful for Liftoff, because by default it falls back
> to TurboFan when it encounters an unimplemented opcode.
>
> Bug: v8:9909

Bug: v8:9909
Change-Id: I7daacbe8b195d9212367190c515b0babbc457a88
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/2018043Reviewed-by: Clemens Backes <clemensb@chromium.org>
Commit-Queue: Zhi An Ng <zhin@chromium.org>
Cr-Commit-Position: refs/heads/master@{#65963}