fix getting field from wrong var

g85/write.py

@@ -42,7 +42,7 @@ def write_wmap(wmap: Map, el_root: ElementTree.Element) -> None:
     map_fields = [ff.name for ff in fields(wmap)]
     for field in map_fields:
         if field[0].isupper():
-            val = getattr(device, field)
+            val = getattr(wmap, field)
             if val is None:
                 continue
             el_map.set(field, val)