This patch moves the clearing of ring data in vnet_port_free_tx_bufs to after
 the freeing of pending buffers in the ring. Otherwise, this can result in
 dereferencing a NULL pointer.
Reported-by: NSowmini Varadhan <sowmini.varadhan@oracle.com>
Signed-off-by: NDavid L Stevens <david.stevens@oracle.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>