[NET] Rename open_request to request_sock

Ok, this one just renames some stuff to have a better namespace and to
dissassociate it from TCP:

struct open_request  -> struct request_sock
tcp_openreq_alloc    -> reqsk_alloc
tcp_openreq_free     -> reqsk_free
tcp_openreq_fastfree -> __reqsk_free

With this most of the infrastructure closely resembles a struct
sock methods subset.

Signed-off-by: Arnaldo Carvalho de Melo <acme@ghostprotocols.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/net/ipv4/tcp_diag.c b/net/ipv4/tcp_diag.c
index 700ff24..6727780 100644
--- a/net/ipv4/tcp_diag.c
+++ b/net/ipv4/tcp_diag.c
@@ -455,7 +455,7 @@
 }
 
 static int tcpdiag_fill_req(struct sk_buff *skb, struct sock *sk,
-			    struct open_request *req,
+			    struct request_sock *req,
 			    u32 pid, u32 seq)
 {
 	const struct inet_request_sock *ireq = inet_rsk(req);
@@ -542,7 +542,7 @@
 	}
 
 	for (j = s_j; j < TCP_SYNQ_HSIZE; j++) {
-		struct open_request *req, *head = lopt->syn_table[j];
+		struct request_sock *req, *head = lopt->syn_table[j];
 
 		reqnum = 0;
 		for (req = head; req; reqnum++, req = req->dl_next) {