[fix] Auto-fill organization from master subnet in SubnetDivisionRule

Author: peterishakvr12

openwisp_controller/subnet_division/base/models.py

@@ -69,6 +69,13 @@ def rule_class(self):
         return import_string(self.type)
 
     def clean(self):
+        # Auto-fill organization from master subnet
+        if (
+        self.master_subnet_id
+        and self.master_subnet.organization is not None
+        and not self.organization
+         ):
+         self.organization = self.master_subnet.organization
         super().clean()
         self._validate_label()
         self._validate_master_subnet_validity()