Bluetooth: Add SMP L2CAP channel skeleton

This patch creates the initial SMP L2CAP channels and a skeleton for
their callbacks. There is one per-adapter channel created upon adapter
registration, and then one channel per-connection created through the
new_connection callback. The channels are registered with the reserved
CID 0x1f for now in order to not conflict with existing SMP
functionality. Once everything is in place the value can be changed to
what it should be, i.e. L2CAP_CID_SMP.

Signed-off-by: Johan Hedberg <johan.hedberg@intel.com>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>

include/net/bluetooth/hci_core.h

@@ -303,6 +303,7 @@ struct hci_dev {
 	__u32			req_result;
 
 	struct crypto_blkcipher	*tfm_aes;
+	void			*smp_data;
 
 	struct discovery_state	discovery;
 	struct hci_conn_hash	conn_hash;

include/net/bluetooth/l2cap.h

@@ -637,6 +637,7 @@ struct l2cap_conn {
 
 	struct delayed_work	security_timer;
 	struct smp_chan		*smp_chan;
+	struct l2cap_chan	*smp;
 
 	struct list_head	chan_l;
 	struct mutex		chan_lock;