[模型训练] 支持r1.3分支resnet50图编译保存和加载，ckpt带策略保存和pangu_alpha续训-同步r1.3分支代码到master

[修改人] haoripei
[审核人] chenshushu

official/cv/resnet/train.py

@@ -357,7 +357,7 @@ def train_net():
 
     # define callbacks
     time_cb = TimeMonitor(data_size=step_size)
-    loss_cb = LossMonitor(config.has_trained_epoch)
+    loss_cb = LossCallBack(config.has_trained_epoch)
     cb = [time_cb, loss_cb]
     ckpt_save_dir = set_save_ckpt_dir()
     if config.save_checkpoint: