drivers/net/irda/kingsun-sir.c: remove null test before kfree

Fix checkpatch warning:
WARNING: kfree(NULL) is safe this check is probably not required

Cc: Samuel Ortiz <samuel@sortiz.org>
Cc: netdev@vger.kernel.org
Signed-off-by: NFabian Frederick <fabf@skynet.be>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

drivers/net/irda/kingsun-sir.c

@@ -553,8 +553,8 @@ static int kingsun_probe(struct usb_interface *intf,
 	return 0;
 
 free_mem:
-	if (kingsun->out_buf) kfree(kingsun->out_buf);
-	if (kingsun->in_buf) kfree(kingsun->in_buf);
+	kfree(kingsun->out_buf);
+	kfree(kingsun->in_buf);
 	free_netdev(net);
 err_out1:
 	return ret;