[llvm] [BOLT][DWARF] Refactor legacy ranges writers (PR #96006)

[Alexander Yermolovich via llvm-commits]

ayermolo wrote:

hmm I was thinking, maybe as a followup PR.
DIE in DWARFRagnes writer doesn't make sense for the instance that handles main binary section. 
Also since for Rangelistswriter inherits from it, for DWARF5 there is a super slight size penalty.
Maybe worth creating another class that inherits from DWARFRangeswriter. Sticking DIE and access APIs there.
Storing that instance in the legacy map.
@maksfb WDYT?

https://github.com/llvm/llvm-project/pull/96006