Staging: cxt1e1: use netdev_priv to fix build

Fix cxt1e1 build error:
drivers/staging/cxt1e1/linux.c:1195: error: 'struct net_device' has no member named 'priv'
Signed-off-by: Randy Dunlap <randy.dunlap@oracle.com>
Acked-by: Bob Beers <bob.beers@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

drivers/staging/cxt1e1/linux.c

@@ -1192,7 +1192,7 @@ c4_add_dev (hdw_info_t * hi, int brdno, unsigned long f0, unsigned long f1,
                 hi->devname, irq1);
         unregister_netdev (ndev);
         free_irq (irq0, ndev);
-        OS_kfree (ndev->priv);
+        OS_kfree (netdev_priv(ndev));
         OS_kfree (ndev);
         error_flag = EIO;
         return 0;