Bluetooth: add recv() callback to l2cap_chan_ops

This abstracts the call to sock_queue_recv_skb() into
l2cap_chan_ops->recv().

Signed-off-by: Gustavo F. Padovan <padovan@profusion.mobi>

include/net/bluetooth/l2cap.h

@@ -363,6 +363,7 @@ struct l2cap_ops {
 	char		*name;
 
 	struct l2cap_chan	*(*new_connection) (void *data);
+	int			(*recv) (void *data, struct sk_buff *skb);
 };
 
 struct l2cap_conn {