[DCCP] ackvec: Fix how DCCP_ACKVEC_STATE_NOT_RECEIVED is used

Fix the way state is masked out.  DCCP_ACKVEC_STATE_NOT_RECEIVED is
defined as appears in the packet, therefore bit shifting is not
required.  This fix allows CCID2 to correctly detect losses.

Signed-off-by: Andrea Bittau <a.bittau@cs.ucl.ac.uk>
Signed-off-by: Arnaldo Carvalho de Melo <acme@mandriva.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/net/dccp/ackvec.c b/net/dccp/ackvec.c
index 8dab723..bc5ff12 100644
--- a/net/dccp/ackvec.c
+++ b/net/dccp/ackvec.c
@@ -436,8 +436,7 @@
 		break;
 found:
 		if (between48(avr->dccpavr_ack_seqno, ackno_end_rl, ackno)) {
-			const u8 state = (*vector &
-					  DCCP_ACKVEC_STATE_MASK) >> 6;
+			const u8 state = *vector & DCCP_ACKVEC_STATE_MASK;
 			if (state != DCCP_ACKVEC_STATE_NOT_RECEIVED) {
 #ifdef CONFIG_IP_DCCP_DEBUG
 				struct dccp_sock *dp = dccp_sk(sk);