[IPV6]: Make fib6_rules_init to return an error code.

When the fib_rules initialization finished, no return code is provided
so there is no way to know, for the caller, if the initialization has
been successful or has failed. This patch fix that.

Signed-off-by: Daniel Lezcano <dlezcano@fr.ibm.com>
Acked-by: Benjamin Thery <benjamin.thery@bull.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/include/net/fib_rules.h b/include/net/fib_rules.h
index 41a301e..2364db1 100644
--- a/include/net/fib_rules.h
+++ b/include/net/fib_rules.h
@@ -103,6 +103,7 @@
 
 extern int			fib_rules_register(struct fib_rules_ops *);
 extern int			fib_rules_unregister(struct fib_rules_ops *);
+extern void                     fib_rules_cleanup_ops(struct fib_rules_ops *);
 
 extern int			fib_rules_lookup(struct fib_rules_ops *,
 						 struct flowi *, int flags,