greth: Remove unnecessary memset of napi member in netdev private data

The memory for the private data is allocated using kzalloc in
alloc_etherdev (or alloc_netdev_mq respectively) so there is no need to
set the napi member to 0 explicitely.
Signed-off-by: NTobias Klauser <tklauser@distanz.ch>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

drivers/net/greth.c

@@ -1555,7 +1555,6 @@ static int __devinit greth_of_probe(struct of_device *ofdev, const struct of_dev
 	}
 
 	/* setup NAPI */
-	memset(&greth->napi, 0, sizeof(greth->napi));
 	netif_napi_add(dev, &greth->napi, greth_poll, 64);
 
 	return 0;