Fix .xm file type recognize error

src/decrypt/xm.js

@@ -1,4 +1,4 @@
-import {AudioMimeType, DetectAudioExt, GetArrayBuffer, GetFileInfo, GetMetaCoverURL, IsBytesEqual} from "./util";
+import {AudioMimeType, GetArrayBuffer, GetFileInfo, GetMetaCoverURL, IsBytesEqual} from "./util";
 
 import {Decrypt as RawDecrypt} from "./raw";
 
@@ -35,7 +35,7 @@ export async function Decrypt(file, raw_filename, raw_ext) {
     for (let cur = dataOffset; cur < lenAudioData; ++cur)
         audioData[cur] = (audioData[cur] - key) ^ 0xff;
 
-    const ext = DetectAudioExt(audioData, "mp3");
+    const ext = FileTypeMap[typeText];
     const mime = AudioMimeType[ext];
     let musicBlob = new Blob([audioData], {type: mime});