model: Fix _validate_status and update_status methods

osmocom/lpmgd/model.py

@@ -42,10 +42,9 @@ class Switcher(abc.ABC):
 
     @staticmethod
     def _validate_status(status: str):
-        if not self._is_valid_status(status):
+        if not Switcher._is_valid_status(status):
             raise ValueError("Invalid Status: %s" % status)
 
-    @staticmethod
     def _update_status(self, status: str):
         """Helper method used by derived class to update status"""
         self._validate_status(status)