Bluetooth: Replace RFCOMM link mode with security level

Change the RFCOMM internals to use the new security levels and remove
the link mode details.

Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
diff --git a/include/net/bluetooth/rfcomm.h b/include/net/bluetooth/rfcomm.h
index 71b45f4..bda68d8 100644
--- a/include/net/bluetooth/rfcomm.h
+++ b/include/net/bluetooth/rfcomm.h
@@ -183,8 +183,8 @@
 	u8            remote_v24_sig;
 	u8            mscex;
 	u8            out;
-
-	u32           link_mode;
+	u8            sec_level;
+	u8            role_switch;
 	u32           defer_setup;
 
 	uint          mtu;
@@ -307,7 +307,8 @@
 	struct bt_sock bt;
 	struct rfcomm_dlc   *dlc;
 	u8     channel;
-	u32    link_mode;
+	u8     sec_level;
+	u8     role_switch;
 };
 
 int  rfcomm_init_sockets(void);