[clang] [compiler-rt] [llvm] [FMV][AArch64] Unify ls64, ls64_v and ls64_accdata. (PR #108024)

[Alexandros Lamprineas via cfe-commits]

labrinea wrote:

This may sound like a bad idea in terms of future maintenance, but how about we guarded the enum entries I am removing with
`#if __FUNCTION_MULTI_VERSIONING_SUPPORT_LEVEL < __ARM_ACLE_VERSION(2024, 3, 0)` ?

https://github.com/llvm/llvm-project/pull/108024