[llvm] [VFABI] Move the Vector ABI demangling utility to LLVMCore. (PR #77513)

[Alexandros Lamprineas via llvm-commits]

labrinea wrote:

> FYI, you don't need to update the files in llvm/utils/gn/secondary. There's a bot that keeps them updated, and they're not officially supported anyways – nothing you need to worry about :)

Right, thanks for letting me know :)

https://github.com/llvm/llvm-project/pull/77513