[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: NDaniel Lezcano <dlezcano@fr.ibm.com>
Acked-by: NYOSHIFUJI Hideaki <yoshfuji@linux-ipv6.org>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

include/net/ip6_fib.h

@@ -226,8 +226,18 @@ extern void			fib6_gc_cleanup(void);
 
 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

net/ipv6/route.c

@@ -2526,11 +2526,10 @@ int __init ip6_route_init(void)
 	if (ret)
 		goto out_proc_init;
 
-#ifdef CONFIG_IPV6_MULTIPLE_TABLES
 	ret = fib6_rules_init();
 	if (ret)
 		goto xfrm6_init;
-#endif
+
 	ret = -ENOBUFS;
 	if (__rtnl_register(PF_INET6, RTM_NEWROUTE, inet6_rtm_newroute, NULL) ||
 	    __rtnl_register(PF_INET6, RTM_DELROUTE, inet6_rtm_delroute, NULL) ||
@@ -2542,10 +2541,8 @@ int __init ip6_route_init(void)
 	return ret;
 
 fib6_rules_init:
-#ifdef CONFIG_IPV6_MULTIPLE_TABLES
 	fib6_rules_cleanup();
 xfrm6_init:
-#endif
 	xfrm6_fini();
 out_proc_init:
 	ipv6_route_proc_fini(&init_net);
@@ -2559,9 +2556,7 @@ int __init ip6_route_init(void)
 
 void ip6_route_cleanup(void)
 {
-#ifdef CONFIG_IPV6_MULTIPLE_TABLES
 	fib6_rules_cleanup();
-#endif
 	ipv6_route_proc_fini(&init_net);
 	xfrm6_fini();
 	rt6_ifdown(NULL);