Bluetooth: Check 'dev_class' in mgmt_device_found()

The mgmt_device_found event will be used to report LE devices found
during discovery procedure. Since LE advertising reports events
doesn't have class of device information, we need to check if
'dev_class' is not NULL before copying it.
Signed-off-by: Andre Guedes <andre.guedes@openbossa.org>
Signed-off-by: Gustavo F. Padovan <padovan@profusion.mobi>

net/bluetooth/mgmt.c

@@ -2324,12 +2324,14 @@ int mgmt_device_found(u16 index, bdaddr_t *bdaddr, u8 *dev_class, s8 rssi,
 	memset(&ev, 0, sizeof(ev));
 
 	bacpy(&ev.bdaddr, bdaddr);
-	memcpy(ev.dev_class, dev_class, sizeof(ev.dev_class));
 	ev.rssi = rssi;
 
 	if (eir)
 		memcpy(ev.eir, eir, sizeof(ev.eir));
 
+	if (dev_class)
+		memcpy(ev.dev_class, dev_class, sizeof(ev.dev_class));
+
 	return mgmt_event(MGMT_EV_DEVICE_FOUND, index, &ev, sizeof(ev), NULL);
 }