gianfar: correct list membership accounting

At a cost of one line let's make sure .count is correct
when calling gfar_process_filer_changes().
Signed-off-by: Jakub Kicinski <kubakici@wp.pl>
Signed-off-by: David S. Miller <davem@davemloft.net>

drivers/net/ethernet/freescale/gianfar_ethtool.c

@@ -1721,13 +1721,14 @@ static int gfar_add_cls(struct gfar_private *priv,
 	}
 
 process:
+	priv->rx_list.count++;
 	ret = gfar_process_filer_changes(priv);
 	if (ret)
 		goto clean_list;
-	priv->rx_list.count++;
 	return ret;
 
 clean_list:
+	priv->rx_list.count--;
 	list_del(&temp->list);
 clean_mem:
 	kfree(temp);