[NETFILTER]: nf_nat: fix memset error

The size passing to memset is the size of a pointer.
Signed-off-by: NLi Zefan <lizf@cn.fujitsu.com>
Signed-off-by: NPatrick McHardy <kaber@trash.net>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

net/ipv4/netfilter/nf_nat_core.c

@@ -681,7 +681,7 @@ static int clean_nat(struct nf_conn *i, void *data)
 
 	if (!nat)
 		return 0;
-	memset(nat, 0, sizeof(nat));
+	memset(nat, 0, sizeof(*nat));
 	i->status &= ~(IPS_NAT_MASK | IPS_NAT_DONE_MASK | IPS_SEQ_ADJUST);
 	return 0;
 }