fix docs

Author: gaopeiliang

docs/en/user_manuals/network.md

@@ -1102,7 +1102,7 @@ HwCloud
 
 ElbIds
 
-- Meaning: the ELB instance ID. You can fill in multiple ids.
+- Meaning: the ELB instance ID. You can fill in multiple ids. （at least one）
 - Value: in the format of elbId-0,elbId-1,... An example value can be "lb-9zeo7prq1m25ctpfrw1m7,lb-bp1qz7h50yd3w58h2f8je"
 - Configuration change supported or not: yes. You can add new elbIds at the end. However, it is recommended not to change existing elbId that is in use.
 
@@ -1207,7 +1207,6 @@ ElbResponseTimeout
 - Format: 1 to 300 default not set, use lb default value
 - Whether to support changes: Yes
 
-
 #### Plugin configuration
 ```
 [hwcloud]

docs/中文/用户手册/网络模型.md

@@ -1043,7 +1043,7 @@ HwCloud
 
 ElbIds
 
-- 含义: elb 的ID, 可填写多个
+- 含义: elb 的ID, 可填写多个 (必须至少1)
 - 填写格式: 例如 "lb-9zeo7prq1m25ctpfrw1m7,lb-bp1qz7h50yd3w58h2f8je"
 - 是否支持变更：支持，只追加