add hub comment

tutorials/source_en/use/multi_platform_inference.md

@@ -101,6 +101,12 @@ MindSpore supports the following inference scenarios based on the hardware platf
         
     `hub.load_weights` is an API for loading model parameters. PLease check the details in <https://www.mindspore.cn/api/en/r0.6/api/python/mindspore/mindspore.hub.html#mindspore.hub.load_weights>.
     
+    if want to use `hub`, need to isntall the requirement package `bs4`. The install as following:
+   
+    ```python
+    pip install bs4
+    ```
+
 2. Use the `model.predict` API to perform inference.
    ```python
    model.predict(input_data)

tutorials/source_zh_cn/use/multi_platform_inference.md

@@ -98,6 +98,10 @@ CPU | ONNX格式 | 支持ONNX推理的runtime/SDK，如TensorRT。
     ``` 
     其中，  
     `hub.load_weights`为加载模型参数接口，对应接口说明：<https://www.mindspore.cn/api/zh-CN/r0.6/api/python/mindspore/mindspore.hub.html#mindspore.hub.load_weights>。
+    使用hub功能接口之前，需要安装bs4依赖包，具体安装代码为：
+    ```python
+    pip install bs4
+    ```
 
 2. 使用`model.predict`接口来进行推理操作。
    ```python