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>
diff --git a/drivers/acpi/video_detect.c b/drivers/acpi/video_detect.c
index 575593a..8c1b43161 100644
--- a/drivers/acpi/video_detect.c
+++ b/drivers/acpi/video_detect.c
@@ -101,7 +101,7 @@
 	/* Only check for backlight functionality if one of the above hit. */
 	if (video_caps)
 		acpi_walk_namespace(ACPI_TYPE_DEVICE, device->handle,
-				    ACPI_UINT32_MAX, acpi_backlight_cap_match,
+				    ACPI_UINT32_MAX, acpi_backlight_cap_match, NULL,
 				    &video_caps, NULL);
 
 	return video_caps;
@@ -151,7 +151,7 @@
 	if (!graphics_handle) {
 		/* Only do the global walk through all graphics devices once */
 		acpi_walk_namespace(ACPI_TYPE_DEVICE, ACPI_ROOT_OBJECT,
-				    ACPI_UINT32_MAX, find_video,
+				    ACPI_UINT32_MAX, find_video, NULL,
 				    &caps, NULL);
 		/* There might be boot param flags set already... */
 		acpi_video_support |= caps;
@@ -173,7 +173,7 @@
 			return 0;
 		}
 		acpi_walk_namespace(ACPI_TYPE_DEVICE, graphics_handle,
-				    ACPI_UINT32_MAX, find_video,
+				    ACPI_UINT32_MAX, find_video, NULL,
 				    &caps, NULL);
 	}
 	ACPI_DEBUG_PRINT((ACPI_DB_INFO, "We have 0x%lX video support %s %s\n",