Bluetooth: Add constants for LTK key types

The LTK key types available right now are unauthenticated and
authenticated ones. Provide two simple constants for it.
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
Signed-off-by: Johan Hedberg <johan.hedberg@intel.com>

include/net/bluetooth/hci.h

@@ -346,6 +346,10 @@ enum {
 #define HCI_SMP_LTK			0x82
 #define HCI_SMP_LTK_SLAVE		0x83
 
+/* Long Term Key types */
+#define HCI_LTK_UNAUTH			0x00
+#define HCI_LTK_AUTH			0x01
+
 /* ---- HCI Error Codes ---- */
 #define HCI_ERROR_AUTH_FAILURE		0x05
 #define HCI_ERROR_CONNECTION_TIMEOUT	0x08