[llvm] [WebAssembly] Remove FAKE_USEs before ExplicitLocals (PR #160228)

[Heejin Ahn via llvm-commits]

aheejin wrote:

That's my understanding. If we reaaaally want to delay this until the very end, we can insert a pass right before the AsmPrinter to essentially convert these to `drop`s, but I don't think it's worth it and we can just rely on ExplicitLocal to do its normal job here.

https://github.com/llvm/llvm-project/pull/160228