update docs

Signed-off-by: Nzengyawen <zengyawen1@huawei.com>

zh-cn/application-dev/media/audio-recorder.md

@@ -127,7 +127,7 @@ import mediaLibrary from '@ohos.multimedia.mediaLibrary'
 
 let testFdNumber;
 
-function SetCallBack(audioPlayer) {
+function SetCallBack(audioRecorder) {
     audioRecorder.on('prepare', () => {              								// 设置'prepare'事件回调
         console.log('prepare success');    
         // 录制界面可切换至已准备好，可点击录制按钮进行录制