Bluetooth: Request L2CAP fixed channel list if available

If the extended features mask indicates support for fixed channels,
request the list of available fixed channels. This also enables the
fixed channel features bit so remote implementations can request
information about it. Currently only the signal channel will be
listed.

Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
diff --git a/include/net/bluetooth/l2cap.h b/include/net/bluetooth/l2cap.h
index 4781d28..abfec88 100644
--- a/include/net/bluetooth/l2cap.h
+++ b/include/net/bluetooth/l2cap.h
@@ -185,6 +185,7 @@
 /* info type */
 #define L2CAP_IT_CL_MTU     0x0001
 #define L2CAP_IT_FEAT_MASK  0x0002
+#define L2CAP_IT_FIXED_CHAN 0x0003
 
 /* info result */
 #define L2CAP_IR_SUCCESS    0x0000