[clang] [WebAssembly] Remove CPU tests from wasm-features.c (PR #80900)

[Heejin Ahn via cfe-commits]

aheejin wrote:

Hmm, on second thought, I think it'd be better to test `-target-cpu` lines instead than deleting the whole thing. Sorry for the flip-flopping.

https://github.com/llvm/llvm-project/pull/80900