ACPICA: Add post-order callback to acpi_walk_namespace

The existing interface only has a pre-order callback. This change
adds an additional parameter for a post-order callback which will
be more useful for bus scans. ACPICA BZ 779.

Also update the external calls to acpi_walk_namespace.

http://www.acpica.org/bugzilla/show_bug.cgi?id=779

Signed-off-by: Lin Ming <ming.m.lin@intel.com>
Signed-off-by: Bob Moore <robert.moore@intel.com>
Signed-off-by: Len Brown <len.brown@intel.com>

arch/ia64/sn/kernel/io_acpi_init.c

@@ -390,7 +390,7 @@ sn_acpi_get_pcidev_info(struct pci_dev *dev, struct pcidev_info **pcidev_info,
 	pcidev_match.handle = NULL;
 
 	acpi_walk_namespace(ACPI_TYPE_DEVICE, rootbus_handle, ACPI_UINT32_MAX,
-			    find_matching_device, &pcidev_match, NULL);
+			    find_matching_device, NULL, &pcidev_match, NULL);
 
 	if (!pcidev_match.handle) {
 		printk(KERN_ERR