Update tests/ui/codegen/target-cpus.rs after upgrading to LLVM 20

[TimNN]

LLVM 20 is adding a new target CPU for WebAssembly (lime1), which changes the output of that test.

#133910 temporarily modifies the test to accept the output of both LLVM versions, but that should be reverted after upgrading to LLVM 20.

@rustbot label: +A-llvm

[IjayAbby]

@rustbot claim