fix arg order

Author: tohtana

deepspeed/runtime/zero/stage_1_and_2.py

@@ -1602,8 +1602,8 @@ def allreduce_and_copy(self,
 
         with get_accelerator().stream(stream):
             allreduced = self.allreduce_bucket(
-                communication_data_type,
                 small_bucket,
+                communication_data_type,
                 rank=rank,
                 log=log,
                 divide=divide,