Bluetooth: Fix sending incorrect LE CoC PDU in BT_CONNECT2 state

For LE CoC L2CAP servers we don't do security level elevation during the
BT_CONNECT2 state (instead LE CoC simply sends an immediate error
response if the security level isn't high enough). Therefore if we get a
security level change while an LE CoC channel is in the BT_CONNECT2
state we should simply do nothing.
Signed-off-by: NJohan Hedberg <johan.hedberg@intel.com>
Signed-off-by: NMarcel Holtmann <marcel@holtmann.org>

net/bluetooth/l2cap_core.c

@@ -7332,7 +7332,8 @@ int l2cap_security_cfm(struct hci_conn *hcon, u8 status, u8 encrypt)
 				l2cap_start_connection(chan);
 			else
 				__set_chan_timer(chan, L2CAP_DISC_TIMEOUT);
-		} else if (chan->state == BT_CONNECT2) {
+		} else if (chan->state == BT_CONNECT2 &&
+			   chan->mode != L2CAP_MODE_LE_FLOWCTL) {
 			struct l2cap_conn_rsp rsp;
 			__u16 res, stat;