net: pcnet: Add initialized eth_device structure

pcnet driver does not have write_hwaddr function.
However, eth stuff executes write_hwaddr function
because eth_device structure has not been initialized.

Signed-off-by: Nobuhiro Iwamatsu <iwamatsu@nigauri.org>
CC: Ben Warren <biggerbadderben@gmail.com>

drivers/net/pcnet.c

@@ -187,6 +187,11 @@ int pcnet_initialize (bd_t * bis)
 		 * Allocate and pre-fill the device structure.
 		 */
 		dev = (struct eth_device *) malloc (sizeof *dev);
+		if (!dev) {
+			printf("pcnet: Can not allocate memory\n");
+			break;
+		}
+		memset(dev, 0, sizeof(*dev));
 		dev->priv = (void *) devbusfn;
 		sprintf (dev->name, "pcnet#%d", dev_nr);