net/neighbour.h: fix typo

'Shoul' must be 'should'.
Signed-off-by: Kulikov Vasiliy <segooon@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

include/net/neighbour.h

@@ -151,7 +151,7 @@ struct neigh_table {
 	void			(*proxy_redo)(struct sk_buff *skb);
 	char			*id;
 	struct neigh_parms	parms;
-	/* HACK. gc_* shoul follow parms without a gap! */
+	/* HACK. gc_* should follow parms without a gap! */
 	int			gc_interval;
 	int			gc_thresh1;
 	int			gc_thresh2;