Revert "fib_rules: fix error in backport of e9919a24 ("fib_rules: return 0...")"

This reverts commit d5c71a7c as the
patch that this "fixes" is about to be reverted...
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

net/core/fib_rules.c

@@ -430,7 +430,6 @@ int fib_nl_newrule(struct sk_buff *skb, struct nlmsghdr *nlh)
 		goto errout_free;
 
 	if (rule_exists(ops, frh, tb, rule)) {
-		err = 0;
 		if (nlh->nlmsg_flags & NLM_F_EXCL)
 			err = -EEXIST;
 		goto errout_free;