[MTD] [NOR] intel_dc21285 switch to ROM API

Now that the needed helpers are exported, it becomes a nice simple 
switch over. Closes #9420
Signed-off-by: NAlan Cox <alan@redhat.com>
Signed-off-by: NDavid Woodhouse <David.Woodhouse@intel.com>

drivers/mtd/maps/pci.c

@@ -203,15 +203,8 @@ intel_dc21285_init(struct pci_dev *dev, struct map_pci_info *map)
 		 * not enabled, should we be allocating a new resource for it
 		 * or simply enabling it?
 		 */
-		if (!(pci_resource_flags(dev, PCI_ROM_RESOURCE) &
-				    IORESOURCE_ROM_ENABLE)) {
-		     	u32 val;
-			pci_resource_flags(dev, PCI_ROM_RESOURCE) |= IORESOURCE_ROM_ENABLE;
-			pci_read_config_dword(dev, PCI_ROM_ADDRESS, &val);
-			val |= PCI_ROM_ADDRESS_ENABLE;
-			pci_write_config_dword(dev, PCI_ROM_ADDRESS, val);
-			printk("%s: enabling expansion ROM\n", pci_name(dev));
-		}
+		pci_enable_rom(dev);
+		printk("%s: enabling expansion ROM\n", pci_name(dev));
 	}
 
 	if (!len || !base)
@@ -240,10 +233,7 @@ intel_dc21285_exit(struct pci_dev *dev, struct map_pci_info *map)
 	/*
 	 * We need to undo the PCI BAR2/PCI ROM BAR address alteration.
 	 */
-	pci_resource_flags(dev, PCI_ROM_RESOURCE) &= ~IORESOURCE_ROM_ENABLE;
-	pci_read_config_dword(dev, PCI_ROM_ADDRESS, &val);
-	val &= ~PCI_ROM_ADDRESS_ENABLE;
-	pci_write_config_dword(dev, PCI_ROM_ADDRESS, val);
+	pci_disable_rom(dev);
 }
 
 static unsigned long