We move the mask to be the first input of the node in wasm-compiler.cc,
this matches the order for S128Select, which makes code-gen for
arm/arm64 simpler (directly lower to BSL with no more shuffle of
inputs). This requires tweaking of input indices in the instruction
selector for ia32/x64, but no change in codegen.

Bug: v8:12284
Change-Id: I1f6f1a9fe0869509be77f77b6f54a0c636a0f92d
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/3272640
Commit-Queue: Zhi An Ng <zhin@chromium.org>
Reviewed-by: Deepti Gandluri <gdeepti@chromium.org>
Cr-Commit-Position: refs/heads/main@{#77958}