[llvm] [CodeGen][ARM64EC] Mangle EH personality handler names (PR #121652)

[Eli Friedman via llvm-commits]

https://github.com/efriedma-quic commented:

Not that it's really likely to matter, but I'd prefer to check the module triple is arm64ec before we try to do arm64ec-specific demangling.

https://github.com/llvm/llvm-project/pull/121652