mfd: use pci_ioremap_bar() in sm501

Use the newly introduced pci_ioremap_bar() function in drivers/mfd.
pci_ioremap_bar() just takes a pci device and a bar number, with the goal
of making it really hard to get wrong, while also having a central place
to stick sanity checks.
Signed-off-by: NArjan van de Ven <arjan@linux.intel.com>
Signed-off-by: NSamuel Ortiz <sameo@openedhand.com>

drivers/mfd/sm501.c

@@ -1625,8 +1625,7 @@ static int sm501_pci_probe(struct pci_dev *dev,
 		goto err3;
 	}
 
-	sm->regs = ioremap(pci_resource_start(dev, 1),
-			   pci_resource_len(dev, 1));
+	sm->regs = pci_ioremap_bar(dev, 1);
 
 	if (sm->regs == NULL) {
 		dev_err(&dev->dev, "cannot remap registers\n");