LibDebug: Implement symbolication for x86_64

Author: https://github.com/gunnarbeutner
Commit: 2c41e89d08
Pull-request: https://github.com/SerenityOS/serenity/pull/8725

Userland/Libraries/LibDebug/Dwarf/LineProgram.cpp

@@ -174,7 +174,7 @@ void LineProgram::handle_extended_opcode()
         break;
     }
     default:
-        dbgln_if(DWARF_DEBUG, "offset: {:p}", m_stream.offset());
+        dbgln("Encountered unknown sub opcode {} at stream offset {:p}", sub_opcode, m_stream.offset());
         VERIFY_NOT_REACHED();
     }
 }