[MERGE #5962 @penzn] [WASM SIMD update, part 3] Update opcodes

Merge pull request #5962 from penzn:wasm.simd.opcodes

Make sure that WebAssembly SIMD opcodes are in sync with
WebAssembly/wabt@bfc4f5b9 which is equivalent to WABT fork in `lib`.

Recompile wasm.simd tests with the version of wabt mentioned above.

For #5838

Author: MikeHolman