Set PCI bus operations at buildtime for ramstage

PCI bus operations are static through the ramstage, and should be
initialized from the very beginning. For all the replaced instances,
there is no MMCONF_SUPPORT nor MMCONF_SUPPORT_DEFAULT selected for
the northbridge, so these continue to use PCI IO config access.

Change-Id: I658abd4a02aa70ad4c9273568eb5560c6e572fb1
Signed-off-by: Kyösti Mälkki <kyosti.malkki@gmail.com>
Reviewed-on: http://review.coreboot.org/3607
Tested-by: build bot (Jenkins)
Reviewed-by: Stefan Reinauer <stefan.reinauer@coreboot.org>

src/cpu/amd/sc520/sc520.c

@@ -161,6 +161,7 @@ static struct device_operations pci_domain_ops = {
         .enable_resources = 0, //enable_resources,
         .init             = 0,
         .scan_bus         = pci_domain_scan_bus,
+        .ops_pci_bus      = pci_bus_default_ops,
 };
 
 #if 0
@@ -188,7 +189,6 @@ static void enable_dev(struct device *dev)
         /* Set the operations if it is a special bus type */
         if (dev->path.type == DEVICE_PATH_DOMAIN) {
                 dev->ops = &pci_domain_ops;
-		pci_set_method(dev);
         }
 #if 0
 	/* This is never hit as none of the sc520 boards have