Bluetooth: Fix 'SendRRorRNR' to send the ReqSeq value

SendRRorRNR needs to acknowledge received I-frames (actually every packet
needs to acknowledge received I-frames by sending the proper packet
sequence number), so ReqSeq is set to the next I-frame number sequence to
be pulled by the reassembly function.
SendRRorRNR tells the remote side about local busy conditions, it sends
a Receiver Ready frame if local busy is false or a Receiver Not Ready
if local busy is true.
ReqSeq is the packet's field to send the number of the acknowledged
packets.

Signed-off-by: Gustavo F. Padovan <gustavo@las.ic.unicamp.br>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>

net/bluetooth/l2cap.c

@@ -373,6 +373,8 @@ static inline int l2cap_send_rr_or_rnr(struct l2cap_pinfo *pi, u16 control)
 	else
 		control |= L2CAP_SUPER_RCV_READY;
 
+	control |= pi->buffer_seq << L2CAP_CTRL_REQSEQ_SHIFT;
+
 	return l2cap_send_sframe(pi, control);
 }