pixma_imageclass: fix for failed first usb command (timeout)

Sometimes the first usb command to the scanner fails after a previous scan.
A workaround was to reconnect the usb cable. This fix simply resends the
failed command.

backend/pixma_imageclass.c

@@ -426,6 +426,11 @@ step1 (pixma_t * s)
   iclass_t *mf = (iclass_t *) s->subdriver;
 
   error = query_status (s);
+  if (error < 0)
+  {
+    PDBG (pixma_dbg (1, "WARNING: Resend first USB command after timeout!\n"));
+    error = query_status (s);
+  }
   if (error < 0)
     return error;
   if (s->param->source == PIXMA_SOURCE_ADF && !has_paper (s))