[clang] [llvm] [AArch64] Implement intrinsics for SME2 FSCALE (PR #100128)

[via cfe-commits]

dyung wrote:

@Lukacma the test you added, CodeGen/aarch64-fp8-intrinsics/acle_sme2_fp8_scale.c, is failing on at least 2 bots, can you take a look and revert if you need time to investigate?

- https://lab.llvm.org/buildbot/#/builders/190/builds/6495
- https://lab.llvm.org/buildbot/#/builders/174/builds/5792

https://github.com/llvm/llvm-project/pull/100128