[llvm] [BOLT] Use symbol table info in registerFragment (PR #89648)

[Amir Ayupov via llvm-commits]

aaupov wrote:

@maksfb: I've addressed the existing concerns – does that look good for you? Note we now depend on #89861 for ELFSymbolRef comparisons. We can add heuristics based on bolt_pseudo.o to make fragment matching even faster in BOLTed binary case as follow-up diffs.

https://github.com/llvm/llvm-project/pull/89648