spidernet : fix memory leak in spider_net_stop

We forget to call spider_net_free_rx_chain_contents which does the
actual dev_kfree_skb. New skbs are allocated from skbuff_head_cache
on each "ifconfig up" letting the cache grow infinitely.

This patch fixes it.
Signed-off-by: NJens Osterkamp <jens@de.ibm.com>
Signed-off-by: NJeff Garzik <jeff@garzik.org>

drivers/net/spider_net.c

@@ -1925,6 +1925,8 @@ spider_net_stop(struct net_device *netdev)
 	/* release chains */
 	spider_net_release_tx_chain(card, 1);
 
+	spider_net_free_rx_chain_contents(card);
+
 	spider_net_free_chain(card, &card->tx_chain);
 	spider_net_free_chain(card, &card->rx_chain);