BatchFileTransfer: Use actual queue size for progress.

app/src/main/java/de/ccc/events/badge/card10/filetransfer/BatchTransferFragment.kt

@@ -58,7 +58,7 @@ class BatchTransferFragment : Fragment(), FileTransferListener, GattListener {
 
     override fun onViewCreated(view: View, savedInstanceState: Bundle?) {
         label_status.text = getString(R.string.batch_transfer_label_initializing)
-        progress.max = 5
+        progress.max = queue.size
 
         button_cancel.setOnClickListener {
             isCancelled = true