[llvm] [LLVM][AARCH64]Replace +sme2p1+smef16f16 by +smef16f16 (PR #88860)

[Tomas Matheson via llvm-commits]

tmatheson-arm wrote:

I have been looking into that, but I think it is too difficult to do. The dependencies are already flattened and scrambled by the `ExtensionBitset` before being output to `-cc1`. Any dependency expansion after that stage is probably going to be impossible to do consistently and will make things more confusing.

https://github.com/llvm/llvm-project/pull/88860