platform/x86: asus-wmi: fix asus ux303ub brightness issue

acpi_video0 doesn't work, asus-wmi brightness interface doesn't work, too.
So, we use native brightness interface to handle the brightness adjustion,
and add quirk_asus_ux303ub.

Signed-off-by: zino lin <linzino7@gmail.com>
Acked-by: Corentin Chary <corentin.chary@gmail.com>
Signed-off-by: Darren Hart <dvhart@linux.intel.com>
diff --git a/drivers/platform/x86/asus-wmi.c b/drivers/platform/x86/asus-wmi.c
index 7c093a0..ce6ca31 100644
--- a/drivers/platform/x86/asus-wmi.c
+++ b/drivers/platform/x86/asus-wmi.c
@@ -2084,6 +2084,9 @@
 	if (asus->driver->quirks->wmi_backlight_power)
 		acpi_video_set_dmi_backlight_type(acpi_backlight_vendor);
 
+	if (asus->driver->quirks->wmi_backlight_native)
+		acpi_video_set_dmi_backlight_type(acpi_backlight_native);
+
 	if (acpi_video_get_backlight_type() == acpi_backlight_vendor) {
 		err = asus_wmi_backlight_init(asus);
 		if (err && err != -ENODEV)