[llvm] [WebAssembly] [Codegen] Add patterns for relaxed dot (PR #163266)

[Jasmine Tang via llvm-commits]

badumbatish wrote:

thanks everyone, i've been waiting for [buildkite/libcxx-ci](https://buildkite.com/llvm-project/libcxx-ci/builds/89604) for a while now, i'm not sure if there's a way to restart it or should i go ahead and bypass it for now?

https://github.com/llvm/llvm-project/pull/163266