update docs

Signed-off-by: Nannie_wangli <annie.wangli@huawei.com>

en/device-dev/driver/driver-hdf-manage.md

@@ -330,8 +330,17 @@ This syntax indicates that the  **attribute**  value is a reference to  **node**
 node1 {
     attributes;
 }
+node2 {
+    attr_1 = &root.node1;
+}
+```
+Or
 
+```
 node2 {
+    node1 {
+        attributes;
+    }
     attr_1 = &node1;
 }
 ```