Bluetooth: Fixes l2cap "command reject" reply according to spec

There can 3 reasons for the "command reject" reply produced
by the stack. Each such reply should be accompanied by the
relevand data ( as defined in spec. ). Currently there is one
instance of "command reject" reply with reason "invalid cid"
wich is fixed. Also, added clean-up definitions related to the
"command reject" replies.

Signed-off-by: Ilia Kolomisnky <iliak@ti.com>
Signed-off-by: Gustavo F. Padovan <padovan@profusion.mobi>

include/net/bluetooth/l2cap.h

@@ -129,6 +129,12 @@ struct l2cap_conninfo {
 #define L2CAP_SDU_END               0x8000
 #define L2CAP_SDU_CONTINUE          0xC000
 
+/* L2CAP Command rej. reasons */
+#define L2CAP_REJ_NOT_UNDERSTOOD      0x0000
+#define L2CAP_REJ_MTU_EXCEEDED        0x0001
+#define L2CAP_REJ_INVALID_CID         0x0002
+
+
 /* L2CAP structures */
 struct l2cap_hdr {
 	__le16     len;
@@ -143,10 +149,21 @@ struct l2cap_cmd_hdr {
 } __packed;
 #define L2CAP_CMD_HDR_SIZE	4
 
-struct l2cap_cmd_rej {
+struct l2cap_cmd_rej_unk {
 	__le16     reason;
 } __packed;
 
+struct l2cap_cmd_rej_mtu {
+	__le16     reason;
+	__le16     max_mtu;
+} __packed;
+
+struct l2cap_cmd_rej_cid {
+	__le16     reason;
+	__le16     scid;
+	__le16     dcid;
+} __packed;
+
 struct l2cap_conn_req {
 	__le16     psm;
 	__le16     scid;