[NETFILTER]: nf_conntrack: add missing unlock in get_next_corpse()

Add missing unlock in get_next_corpse() in nf_conntrack. It was missed
during the removal of listhelp.h . Also remove an unneeded use of
nf_ct_tuplehash_to_ctrack() in the same function.

Should be applied before 2.6.19 is released.
Signed-off-by: Martin Josefsson <gandalf@wlug.westbo.se>
Signed-off-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: David S. Miller <davem@davemloft.net>

net/netfilter/nf_conntrack_core.c

@@ -1520,9 +1520,10 @@ get_next_corpse(int (*iter)(struct nf_conn *i, void *data),
 		if (iter(ct, data))
 			goto found;
 	}
+	write_unlock_bh(&nf_conntrack_lock);
 	return NULL;
 found:
-	atomic_inc(&nf_ct_tuplehash_to_ctrack(h)->ct_general.use);
+	atomic_inc(&ct->ct_general.use);
 	write_unlock_bh(&nf_conntrack_lock);
 	return ct;
 }