PPC/s390: [wasm] Introducing F16 SIMD lane instructions

Port e8f70212

Original Commit Message:

    The CL introduces F16x8Splat, F16x8ExtractLane and F16x8ReplaceLane
    opcodes together with software implementation in Liftoff.

R=irezvov@chromium.org, joransiu@ca.ibm.com, junyan@redhat.com, midawson@redhat.com
BUG=
LOG=N

Change-Id: I3532d89122e4d67034398c609ce3c17bc46da037
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/5725501


Commit-Queue: Milad Farazmand <mfarazma@redhat.com>
Reviewed-by: Junliang Yan <junyan@redhat.com>
Cr-Commit-Position: refs/heads/main@{#95138}