net: lapbether: fix double free

The function netdev_priv() returns the private data of the device. The
memory to store the private data is allocated in alloc_netdev() and is
released in netdev_free(). Calling kfree() on the return value of
netdev_priv() after netdev_free() results in a double free bug.

Signed-off-by: Pan Bian <[e-mail]>
Signed-off-by: David S. Miller <[e-mail]>

drivers/net/wan/lapbether.c

···
 fail:
 	dev_put(dev);
 	free_netdev(ndev);
-	kfree(lapbeth);
 	goto out;
 }