update docs

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

en/application-dev/reference/apis/js-apis-wifiext.md

+# WLAN
+
+> ![icon-note.gif](public_sys-resources/icon-note.gif) **NOTE**<br/>
+> The initial APIs of this module are supported since API version 8. Newly added APIs will be marked with a superscript to indicate their earliest API version.
+The APIs described in this document are used only for non-universal products, such as routers.
+
+
+## Modules to Import
+
+```js
+import wifiext from '@ohos.wifiext';
+```
+
+## wifiext.enableHotspot
+
+enableHotspot(): boolean;
+
+Enables the WLAN hotspot.
+
+- Required permissions:
+  ohos.permission.MANAGE_WIFI_HOTSPOT_EXT
+
+- System capability:
+  SystemCapability.Communication.WiFi.HotspotExt
+
+- Return value
+  | **Type**| **Description**|
+  | -------- | -------- |
+  | boolean | Returns **true** if the operation is successful; returns **false** otherwise.|
+
+
+## wifiext.disableHotspot
+
+disableHotspot(): boolean;
+
+Disables the WLAN hotspot.
+
+- Required permissions:
+  ohos.permission.MANAGE_WIFI_HOTSPOT_EXT
+
+- System capability:
+  SystemCapability.Communication.WiFi.HotspotExt
+
+- Return value
+  | **Type**| **Description**|
+  | -------- | -------- |
+  | boolean | Returns **true** if the operation is successful; returns **false** otherwise.|
+
+
+## wifiext.getSupportedPowerModel
+
+getSupportedPowerModel(): Promise&lt;Array&lt;PowerModel&gt;&gt;
+
+Obtains the supported power models. The method uses a promise to return the result.
+
+- Required permissions:
+  ohos.permission.GET_WIFI_INFO
+
+- System capability:
+  SystemCapability.Communication.WiFi.HotspotExt
+
+- Return value
+  | Type| Description|
+  | -------- | -------- |
+  | Promise&lt;Array&lt;[PowerModel](#PowerModel)&gt;&gt; | Promise used to return the power models obtained.|
+
+
+## PowerModel
+
+Enumerates of the power models.
+
+| Name| Default Value| Description|
+| -------- | -------- | -------- |
+| SLEEPING | 0 | Sleeping|
+| GENERAL | 1 | General|
+| THROUGH_WALL | 2 | Through_wall|
+
+
+## wifiext.getSupportedPowerModel
+
+getSupportedPowerModel(callback: AsyncCallback&lt;Array&lt;PowerModel&gt;&gt;): void
+
+Obtains the supported power models. The method uses an asynchronous callback to return the result.
+
+- Required permissions:
+  ohos.permission.GET_WIFI_INFO
+
+- System capability:
+  SystemCapability.Communication.WiFi.HotspotExt
+
+- Parameters
+  | Name| Type| Mandatory| Description|
+  | -------- | -------- | -------- | -------- |
+  | callback | AsyncCallback&lt;[PowerModel](#PowerModel)&gt; | Yes| Callback used to return the power models obtained.|
+
+
+## wifiext.getPowerModel
+
+getPowerModel(): Promise&lt;PowerModel&gt;
+
+Obtains the power model. The method uses a promise to return the result.
+
+- Required permissions:
+  ohos.permission.GET_WIFI_INFO
+
+- System capability:
+  SystemCapability.Communication.WiFi.HotspotExt
+
+- Return value
+  | Type| Description|
+  | -------- | -------- |
+  | Promise&lt;[PowerModel](#PowerModel)&gt; | Promise used to return the power model obtained.|
+
+
+## wifiext.getPowerModel
+
+getPowerModel(callback: AsyncCallback&lt;PowerModel&gt;): void
+
+Obtains the power model. The method uses an asynchronous callback to return the result.
+
+- Required permissions:
+  ohos.permission.GET_WIFI_INFO
+
+- System capability:
+  SystemCapability.Communication.WiFi.HotspotExt
+
+- Parameters
+  | Name| Type| Mandatory| Description|
+  | -------- | -------- | -------- | -------- |
+  | callback | AsyncCallback&lt;[PowerModel](#PowerModel)&gt; | Yes| Callback invoked to return the power mode obtained.|
+
+
+## wifiext.setPowerModel
+
+setPowerModel(model: PowerModel) : boolean;
+
+ Sets the power model.
+
+- Required permissions:
+  ohos.permission.MANAGE_WIFI_HOTSPOT_EXT
+
+- System capability:
+  SystemCapability.Communication.WiFi.HotspotExt
+
+- Parameters
+  | Name| Type| Mandatory| Description|
+  | -------- | -------- | -------- | -------- |
+  | model | AsyncCallback&lt;[PowerModel](#PowerModel)&gt; | Yes| Power model to set.|
+
+- Return value
+  | **Type**| **Description**|
+  | -------- | -------- |
+  | boolean | Returns **true** if the operation is successful; returns **false** otherwise.|