[llvm] [BOLT][DWARF][NFC] Refactor address writers (PR #98094)

[Alexander Yermolovich via llvm-commits]

================
@@ -408,14 +434,17 @@ class DebugAddrWriter {
   }
 
   BinaryContext *BC;
-  /// Maps DWOID to AddressForDWOCU.
-  std::unordered_map<uint64_t, AddressForDWOCU> AddressMaps;
+  /// Address for the DWO CU associated with the address writer.
+  AddressForDWOCU Map;
+  uint8_t AddressByteSize;
+  std::optional<uint64_t> AddrOffsetSectionBase;
+  static constexpr uint32_t HeaderSize = 8;
----------------
ayermolo wrote:

Move this to DebugAddrWriterDwarf5 since that's what actually has headers.

https://github.com/llvm/llvm-project/pull/98094