drivers/net/cpmac.c: Correct code taking the size of a pointer

sizeof(dev->dev_addr) is the size of a pointer.  On the other hand,
sizeof(pdata->dev_addr) is the size of an array, so use that instead.

A simplified version of the semantic patch that finds this problem is as
follows: (http://coccinelle.lip6.fr/)

// <smpl>
@@
expression *x;
expression f;
type T;
@@

*f(...,(T)x,...)
// </smpl>
Signed-off-by: Julia Lawall <julia@diku.dk>
Signed-off-by: David S. Miller <davem@davemloft.net>

drivers/net/cpmac.c

@@ -1163,7 +1163,7 @@ static int __devinit cpmac_probe(struct platform_device *pdev)
 	priv->dev = dev;
 	priv->ring_size = 64;
 	priv->msg_enable = netif_msg_init(debug_level, 0xff);
-	memcpy(dev->dev_addr, pdata->dev_addr, sizeof(dev->dev_addr));
+	memcpy(dev->dev_addr, pdata->dev_addr, sizeof(pdata->dev_addr));
 
 	snprintf(priv->phy_name, MII_BUS_ID_SIZE, PHY_ID_FMT, mdio_bus_id, phy_id);