Bluetooth: btusb: mediatek: move Bluetooth power off command position

Move MediaTek Bluetooth power off command before releasing
usb ISO interface.

Signed-off-by: Chris Lu <chris.lu@mediatek.com>
Signed-off-by: Luiz Augusto von Dentz <luiz.von.dentz@intel.com>

drivers/bluetooth/btusb.c

@@ -2709,11 +2709,14 @@ static int btusb_mtk_shutdown(struct hci_dev *hdev)
 {
 	struct btusb_data *data = hci_get_drvdata(hdev);
 	struct btmtk_data *btmtk_data = hci_get_priv(hdev);
+	int ret;
+
+	ret = btmtk_usb_shutdown(hdev);
 
 	if (test_bit(BTMTK_ISOPKT_RUNNING, &btmtk_data->flags))
 		btusb_mtk_release_iso_intf(data);
 
-	return btmtk_usb_shutdown(hdev);
+	return ret;
 }
 
 #ifdef CONFIG_PM