[DCCP]: Tidy up unused structures

This removes and cleans up unused variables and structures which have become
unnecessary following the introduction of the EWMA patch to automatically track
the CCID 3 receiver/sender packet sizes `s'.

It deprecates the PACKET_SIZE socket option by returning an error code and
printing a deprecation warning if an application tries to read or write this
socket option.

Signed-off-by: Gerrit Renker <gerrit@erg.abdn.ac.uk>
Signed-off-by: Arnaldo Carvalho de Melo <acme@mandriva.com>
diff --git a/net/dccp/proto.c b/net/dccp/proto.c
index 3c44d50..2604e34 100644
--- a/net/dccp/proto.c
+++ b/net/dccp/proto.c
@@ -470,7 +470,8 @@
 	lock_sock(sk);
 	switch (optname) {
 	case DCCP_SOCKOPT_PACKET_SIZE:
-		dp->dccps_packet_size = val;
+		DCCP_WARN("sockopt(PACKET_SIZE) is deprecated: fix your app\n");
+		err = -EINVAL;
 		break;
 	case DCCP_SOCKOPT_CHANGE_L:
 		if (optlen != sizeof(struct dccp_so_feat))
@@ -581,9 +582,8 @@
 
 	switch (optname) {
 	case DCCP_SOCKOPT_PACKET_SIZE:
-		val = dp->dccps_packet_size;
-		len = sizeof(dp->dccps_packet_size);
-		break;
+		DCCP_WARN("sockopt(PACKET_SIZE) is deprecated: fix your app\n");
+		return -EINVAL;
 	case DCCP_SOCKOPT_SERVICE:
 		return dccp_getsockopt_service(sk, len,
 					       (__be32 __user *)optval, optlen);