Bluetooth: Ignore SMP data on non-LE links

The SMP CID is only defined for LE transports. Instead of returning an
error from smp_sig_channel() in this case (which would cause a
disconnection) just return 0 to ignore the data, which is consistent
with the behavior for other unknown CIDs.
Signed-off-by: Johan Hedberg <johan.hedberg@intel.com>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>

net/bluetooth/smp.c

@@ -856,7 +856,7 @@ int smp_sig_channel(struct l2cap_conn *conn, struct sk_buff *skb)
 
 	if (hcon->type != LE_LINK) {
 		kfree_skb(skb);
-		return -ENOTSUPP;
+		return 0;
 	}
 
 	if (skb->len < 1) {