!9454 fix hccl init in resnext50

From: @zhouyaqiang0
Reviewed-by: @c_34,@guoqi1024
Signed-off-by: @c_34

model_zoo/official/cv/resnext50/train.py

@@ -147,6 +147,8 @@ def parse_args(cloud_args=None):
     args.lr_epochs = list(map(int, args.lr_epochs.split(',')))
     args.image_size = list(map(int, args.image_size.split(',')))
 
+    context.set_context(mode=context.GRAPH_MODE, enable_auto_mixed_precision=True,
+                        device_target=args.platform, save_graphs=False)
     # init distributed
     if args.is_distributed:
         init()
@@ -190,8 +192,6 @@ def merge_args(args, cloud_args):
 def train(cloud_args=None):
     """training process"""
     args = parse_args(cloud_args)
-    context.set_context(mode=context.GRAPH_MODE, enable_auto_mixed_precision=True,
-                        device_target=args.platform, save_graphs=False)
     if os.getenv('DEVICE_ID', "not_set").isdigit():
         context.set_context(device_id=int(os.getenv('DEVICE_ID')))