[DECNET]: Increase number of possible routing tables to 2^32

Increase the number of possible routing tables to 2^32 by replacing the
fixed sized array of pointers by a hash table and replacing iterations
over all possible table IDs by hash table walking.

Signed-off-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/include/net/dn_fib.h b/include/net/dn_fib.h
index cd9c378..d97aa10 100644
--- a/include/net/dn_fib.h
+++ b/include/net/dn_fib.h
@@ -94,6 +94,7 @@
 
 
 struct dn_fib_table {
+	struct hlist_node hlist;
 	u32 n;
 
 	int (*insert)(struct dn_fib_table *t, struct rtmsg *r, 
@@ -177,8 +178,6 @@
 		fib_rule_put(res->r);
 }
 
-extern struct dn_fib_table *dn_fib_tables[];
-
 #else /* Endnode */
 
 #define dn_fib_init()  do { } while(0)