[IPV6] net/ipv6/ndisc.c: remove unused variable

The variable hlen is initialized but never used otherwise.

The semantic patch that makes this change is as follows:
(http://www.emn.fr/x-info/coccinelle/)

// <smpl>
@@
type T;
identifier i;
constant C;
@@

(
extern T i;
|
- T i;
  <+... when != i
- i = C;
  ...+>
)
// </smpl>
Signed-off-by: NJulia Lawall <julia@diku.dk>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

net/ipv6/ndisc.c

@@ -1420,7 +1420,6 @@ void ndisc_send_redirect(struct sk_buff *skb, struct neighbour *neigh,
 	u8 *opt;
 	int rd_len;
 	int err;
-	int hlen;
 	u8 ha_buf[MAX_ADDR_LEN], *ha = NULL;
 
 	dev = skb->dev;
@@ -1491,7 +1490,6 @@ void ndisc_send_redirect(struct sk_buff *skb, struct neighbour *neigh,
 		return;
 	}
 
-	hlen = 0;
 
 	skb_reserve(buff, LL_RESERVED_SPACE(dev));
 	ip6_nd_hdr(sk, buff, dev, &saddr_buf, &ipv6_hdr(skb)->saddr,