[lld] [LLD][COFF] Check both mangled and demangled symbols before adding a lazy archive symbol to the symbol table on ARM64EC (PR #113284)

[Jacek Caban via llvm-commits]

cjacek wrote:

Depends on #113283.

The primary example of this issue occurs when `func` is present in both a regular archive and an import library. Without this fix, both can be pulled, leading to an error regarding replaced symbols in `appendImportThunks`.

https://github.com/llvm/llvm-project/pull/113284