smsc911x: fix calculation of res_size for ioremap

fix size of remaped iomem, which is 1 byte to small
(e.g. mappes only 0xff bytes instead of 0x100)

Signed-off-by: Matthias Ludwig <mludwig@ultratronik.de>
Acked-by: Steve Glendinning <steve.glendinning@smsc.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

drivers/net/smsc911x.c

@@ -1976,7 +1976,7 @@ static int __devinit smsc911x_drv_probe(struct platform_device *pdev)
 		retval = -ENODEV;
 		goto out_0;
 	}
-	res_size = res->end - res->start;
+	res_size = res->end - res->start + 1;
 
 	irq_res = platform_get_resource(pdev, IORESOURCE_IRQ, 0);
 	if (!irq_res) {