!213 unify vm/ge default fusion group interface

Merge pull request !213 from kisnwang/incmaster

mindspore/parallel/_auto_parallel_context.py

@@ -274,10 +274,7 @@ class _AutoParallelContext:
 
         self._context_handle.set_all_reduce_fusion_split_indices(indices, group)
         if context.get_context("device_target") == "Ascend":
-            if group == "":
-                _set_fusion_strategy_by_idx(indices)
-            else:
-                _set_fusion_strategy_by_idx(indices, group)
+            _set_fusion_strategy_by_idx(indices)
 
     def get_all_reduce_fusion_split_indices(self, group="hccl_world_groupsum1"):
         """
@@ -330,10 +327,7 @@ class _AutoParallelContext:
 
         self._context_handle.set_all_reduce_fusion_split_sizes(sizes, group)
         if context.get_context("device_target") == "Ascend":
-            if group == "":
-                _set_fusion_strategy_by_size(sizes)
-            else:
-                _set_fusion_strategy_by_size(sizes, group)
+            _set_fusion_strategy_by_size(sizes)
 
     def get_all_reduce_fusion_split_sizes(self, group="hccl_world_groupsum1"):
         """