net: sched: return -ENOENT when trying to remove filter from non-existent chain

When chain 0 was implicitly created, removal of non-existent filter from
chain 0 gave -ENOENT. Once chain 0 became non-implicit, the same call is
giving -EINVAL. Fix this by returning -ENOENT in that case.
Reported-by: NRoman Mashak <mrv@mojatatu.com>
Fixes: f71e0ca4 ("net: sched: Avoid implicit chain 0 creation")
Signed-off-by: NJiri Pirko <jiri@mellanox.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

net/sched/cls_api.c

@@ -1399,7 +1399,7 @@ static int tc_del_tfilter(struct sk_buff *skb, struct nlmsghdr *n,
 			goto errout;
 		}
 		NL_SET_ERR_MSG(extack, "Cannot find specified filter chain");
-		err = -EINVAL;
+		err = -ENOENT;
 		goto errout;
 	}