[lld] [lld][WebAssembly] Allow `--trace-symbol` to work with symbols with custom import names (PR #96119)

[Heejin Ahn via llvm-commits]

aheejin wrote:

> > * Is the intention to print the import name, not the internal name in tracing?
> 
> Yes exactly. Imagine I have a symbols called `__internal_fd_write` which is imported as `fd_write` (i.e. the symbol `__internal_fd_write` has an import name of `fd_write`.
> 
> Prior to this change, if a user links with `--trace-symbol=fd_write` they would see no output when this import is used.
> 
> After this change they would see a report of `fd_write` being undefined/imported in a certain object file.

What if we have another symbol (which is may or may not be imported) whose name is `fd_write`? Then if a user specifies `fd_write`, does that point to the symbol with that name or this symbol whose import name is `fd_write`? Is this even possible?

https://github.com/llvm/llvm-project/pull/96119