[IPV6]: route6 remove ifdef for fib_rules

The patch defines the usual static inline functions when the code is
disabled for fib6_rules. That's allow to remove some ifdef in route.c
file and make the code a little more clear.

Signed-off-by: Daniel Lezcano <dlezcano@fr.ibm.com>
Acked-by: YOSHIFUJI Hideaki <yoshfuji@linux-ipv6.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/include/net/ip6_fib.h b/include/net/ip6_fib.h
index eaa3158..14830ed 100644
--- a/include/net/ip6_fib.h
+++ b/include/net/ip6_fib.h
@@ -226,8 +226,18 @@
 
 extern int			fib6_init(void);
 
+#ifdef CONFIG_IPV6_MULTIPLE_TABLES
 extern int			fib6_rules_init(void);
 extern void			fib6_rules_cleanup(void);
-
+#else
+static inline int               fib6_rules_init(void)
+{
+	return 0;
+}
+static inline void              fib6_rules_cleanup(void)
+{
+	return ;
+}
+#endif
 #endif
 #endif