[UDP]: Revert 2-pass hashing changes.

This reverts changesets:

6aaf47fa48d3c44280810b1b470261d340e4ed87
b7b5f487ab39bc10ed0694af35651a03d9cb97ff
de34ed91c4ffa4727964a832c46e624dd1495cf5
fc038410b4b1643766f8033f4940bcdb1dace633

There are still some correctness issues recently
discovered which do not have a known fix that doesn't
involve doing a full hash table scan on port bind.

So revert for now.

Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/net/ipv6/udp.c b/net/ipv6/udp.c
index d1fbddd..4210951 100644
--- a/net/ipv6/udp.c
+++ b/net/ipv6/udp.c
@@ -52,28 +52,9 @@
 
 DEFINE_SNMP_STAT(struct udp_mib, udp_stats_in6) __read_mostly;
 
-static int ipv6_rcv_saddr_any(const struct sock *sk)
-{
-	struct ipv6_pinfo *np = inet6_sk(sk);
-
-	return ipv6_addr_any(&np->rcv_saddr);
-}
-
-static unsigned int ipv6_hash_port_and_rcv_saddr(__u16 port,
-						 const struct sock *sk)
-{
-	return port;
-}
-
-const struct udp_get_port_ops udp_ipv6_ops = {
-	.saddr_cmp = ipv6_rcv_saddr_equal,
-	.saddr_any = ipv6_rcv_saddr_any,
-	.hash_port_and_rcv_saddr = ipv6_hash_port_and_rcv_saddr,
-};
-
 static inline int udp_v6_get_port(struct sock *sk, unsigned short snum)
 {
-	return udp_get_port(sk, snum, &udp_ipv6_ops);
+	return udp_get_port(sk, snum, ipv6_rcv_saddr_equal);
 }
 
 static struct sock *__udp6_lib_lookup(struct in6_addr *saddr, __be16 sport,