inet: rename some inet_sock fields

In order to have better cache layouts of struct sock (separate zones
for rx/tx paths), we need this preliminary patch.

Goal is to transfert fields used at lookup time in the first
read-mostly cache line (inside struct sock_common) and move sk_refcnt
to a separate cache line (only written by rx path)

This patch adds inet_ prefix to daddr, rcv_saddr, dport, num, saddr,
sport and id fields. This allows a future patch to define these
fields as macros, like sk_refcnt, without name clashes.

Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/net/ipv4/tcp_output.c b/net/ipv4/tcp_output.c
index fcd278a..2e2eb74 100644
--- a/net/ipv4/tcp_output.c
+++ b/net/ipv4/tcp_output.c
@@ -661,8 +661,8 @@
 
 	/* Build TCP header and checksum it. */
 	th = tcp_hdr(skb);
-	th->source		= inet->sport;
-	th->dest		= inet->dport;
+	th->source		= inet->inet_sport;
+	th->dest		= inet->inet_dport;
 	th->seq			= htonl(tcb->seq);
 	th->ack_seq		= htonl(tp->rcv_nxt);
 	*(((__be16 *)th) + 6)	= htons(((tcp_header_size >> 2) << 12) |