Update driver-parameters.md

Author: andyzhangx

docs/driver-parameters.md

@@ -65,7 +65,7 @@ mountPermissions | mounted folder permissions. The default is `0777`, if set as
 --- | **Following parameters are only for vnet setting, e.g. NFS, private endpoint** | --- | --- |
 vnetResourceGroup | specify vnet resource group where virtual network is | existing resource group name | No | if empty, driver will use the `vnetResourceGroup` value in azure cloud config file
 vnetName | virtual network name | existing virtual network name | No | if empty, driver will use the `vnetName` value in azure cloud config file
-subnetName | subnet name | existing subnet name(s) of virtual network, if you want to update service endpoints on multiple subnets, separate them using a comma (`,`) | No | if empty, driver will use the `subnetName` value in azure cloud config file
+subnetName | subnet name | existing subnet name(s) of virtual network, if you want to update service endpoints on multiple subnets, separate them using a comma (`,`) | No | if empty, driver will update all the subnets under the cluster virtual network
 fsGroupChangePolicy | indicates how volume's ownership will be changed by the driver, pod `securityContext.fsGroupChangePolicy` is ignored  | `OnRootMismatch`(by default), `Always`, `None` | No | `OnRootMismatch`
 
  - account tags format created by dynamic provisioning