Fix bug calling a self method. See ietf-tools#618

 - Legacy-Id: 2891

Author: emiliosanchez

ietf/submit/models.py

@@ -53,7 +53,7 @@ def create_hash(self):
 
     def get_hash(self):
         if not self.submission_hash:
-            create_hash()
+            self.create_hash()
             self.save()
         return self.submission_hash