can: gs_usb: gs_destroy_candev(): fix use after free

This patch fixes a use after free of "dev" in gs_destroy_candev().

Reported-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
diff --git a/drivers/net/can/usb/gs_usb.c b/drivers/net/can/usb/gs_usb.c
index c9f1f99..04b0f84 100644
--- a/drivers/net/can/usb/gs_usb.c
+++ b/drivers/net/can/usb/gs_usb.c
@@ -826,8 +826,8 @@
 {
 	unregister_candev(dev->netdev);
 	free_candev(dev->netdev);
-	kfree(dev);
 	usb_kill_anchored_urbs(&dev->tx_submitted);
+	kfree(dev);
 }
 
 static int gs_usb_probe(struct usb_interface *intf, const struct usb_device_id *id)