[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>

net/ipv6/fib6_rules.c

@@ -265,10 +265,23 @@ static int __init fib6_default_rules_init(void)
 	return 0;
 }
 
-void __init fib6_rules_init(void)
+int __init fib6_rules_init(void)
 {
-	BUG_ON(fib6_default_rules_init());
-	fib_rules_register(&fib6_rules_ops);
+	int ret;
+
+	ret = fib6_default_rules_init();
+	if (ret)
+		goto out;
+
+	ret = fib_rules_register(&fib6_rules_ops);
+	if (ret)
+		goto out_default_rules_init;
+out:
+	return ret;
+
+out_default_rules_init:
+	fib_rules_cleanup_ops(&fib6_rules_ops);
+	goto out;
 }
 
 void fib6_rules_cleanup(void)