[11.0][FIX] mrp_multi_level:

* calendar defined only in warehouse.
 * remove raw query.

mrp_multi_level/models/mrp_area.py

@@ -19,5 +19,8 @@ class MrpArea(models.Model):
         required=True,
     )
     active = fields.Boolean(default=True)
-    calendar_id = fields.Many2one('resource.calendar',
-                                  'Working Hours')
+    calendar_id = fields.Many2one(
+        comodel_name='resource.calendar',
+        string='Working Hours',
+        related='warehouse_id.calendar_id',
+    )