Disable firmware video brightness change on AC/Battery switch by default

-- mjg59

diff --git a/drivers/acpi/video.c b/drivers/acpi/video.c
index bac2901..93b1a9e 100644
--- a/drivers/acpi/video.c
+++ b/drivers/acpi/video.c
@@ -1818,7 +1818,7 @@ static int acpi_video_bus_put_devices(struct acpi_video_bus *video)
 
 static int acpi_video_bus_start_devices(struct acpi_video_bus *video)
 {
-	return acpi_video_bus_DOS(video, 0, 0);
+	return acpi_video_bus_DOS(video, 0, 1);
 }
 
 static int acpi_video_bus_stop_devices(struct acpi_video_bus *video)