deviceEigerP11.py: declare `_recount_steps` as a static method

kamzik3/devices/deviceEigerP11.py

@@ -346,8 +346,9 @@ class EigerScanner(DeviceScanner):
         DeviceScanner.__init__(self, device_id, config)
         self.connect()
 
+    @staticmethod
     def _recount_steps(
-        self, parent_macro: Macro, to_link: Optional[Union[Scan, Step]] = None
+        parent_macro: Macro, to_link: Optional[Union[Scan, Step]] = None
     ) -> int:
         total_frames = 1
         for link in parent_macro.chain: