net: wan: dlci: Remove set but not used variable 'err'

Fixes the following W=1 kernel build warning(s):

 drivers/net/wan/dlci.c: In function ‘dlci_close’:
 drivers/net/wan/dlci.c:298:8: warning: variable ‘err’ set but not used [-Wunused-but-set-variable]

Cc: "David S. Miller" <[email protected]>
Cc: Jakub Kicinski <[email protected]>
Cc: Mike McLagan <[email protected]>
Cc: [email protected]
Signed-off-by: Lee Jones <[email protected]>
Signed-off-by: David S. Miller <[email protected]>

Author: Lee Jones

drivers/net/wan/dlci.c

@@ -295,14 +295,13 @@ static int dlci_close(struct net_device *dev)
 {
 	struct dlci_local	*dlp;
 	struct frad_local	*flp;
-	int			err;
 
 	netif_stop_queue(dev);
 
 	dlp = netdev_priv(dev);
 
 	flp = netdev_priv(dlp->slave);
-	err = (*flp->deactivate)(dlp->slave, dev);
+	(*flp->deactivate)(dlp->slave, dev);
 
 	return 0;
 }