Exit transition immediately if already in the desired state.

sleekxmpp/thirdparty/statemachine.py

@@ -90,6 +90,9 @@ class StateMachine(object):
                 log.debug("Could not acquire lock")
                 return False
 
+        if self.__current_state == to_state:
+            return True
+
         while not self.__current_state in from_states:
             # detect timeout:
             remainder = start + wait - time.time()