Remove no more needed migration of operator in Rule

trytond/ir/rule.py

@@ -112,17 +112,6 @@ class Rule(ModelSQL, ModelView):
                 'invalid_domain': 'Invalid domain',
                 })
 
-    @classmethod
-    def __register__(cls, module_name):
-        cursor = Transaction().cursor
-
-        super(Rule, cls).__register__(module_name)
-
-        # Migration from 2.0: rename operator '<>' into '!='
-        cursor.execute('UPDATE "%s" '
-            'SET operator = %%s '
-            'WHERE operator = %%s' % cls._table, ('!=', '<>'))
-
     @classmethod
     def check_domain(cls, rules):
         ctx = cls._get_context()