!16571 Enable Graph Kernel for EfficientNet on GPU

From: @lishanni513
Reviewed-by: @gaoxiong1,@ckey_dou,@dylangeng
Signed-off-by: @ckey_dou,@dylangeng

model_zoo/official/cv/efficientnet/train.py

@@ -165,6 +165,9 @@ def main():
                   amp_level=cfg.amp_level
                   )
 
+    if args.GPU:
+        context.set_context(enable_graph_kernel=True)
+
 #    callbacks = callbacks if is_master else []
 
     if args.resume: