[BOLT] Ignore special symbols as function aliases in updateELFSymbolTable

Exempt special symbols (hot text/data and _end symbol) from normal
handling. We only need to set their value and make them absolute.

If these symbols are handled as normal symbols and if they alias
functions we may create non-sensical symbols, e.g. __hot_start.cold.

Test Plan: updated hot-end-symbol.s

Reviewers: maksfb, rafaelauler, ayermolo, dcci

Reviewed By: dcci, maksfb

Pull Request: https://github.com/llvm/llvm-project/pull/92713