[llvm] [WebAssembly] avoid to enable explicit disabled feature (PR #80094)

[Thomas Lively via llvm-commits]

https://github.com/tlively commented:

What should happen if a feature is explicitly disabled via globally, but enabled on one of the functions in the module? IIUC, this current patch will have the string to enable it followed by the string to disable it. Which one wins? I think it would be good to have the feature enabled in that case.

https://github.com/llvm/llvm-project/pull/80094