drm: i915: Port to new backlight interface selection API

This results in a nice cleanup, as we can replace the complicated logic
from should_ignore_backlight_request() with a simple check for the type
being native.

Signed-off-by: Hans de Goede <hdegoede@redhat.com>
Acked-by: Darren Hart <dvhart@linux.intel.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>

drivers/gpu/drm/i915/intel_opregion.c

@@ -396,16 +396,6 @@ int intel_opregion_notify_adapter(struct drm_device *dev, pci_power_t state)
 	return -EINVAL;
 }
 
-/*
- * If the vendor backlight interface is not in use and ACPI backlight interface
- * is broken, do not bother processing backlight change requests from firmware.
- */
-static bool should_ignore_backlight_request(void)
-{
-	return acpi_video_backlight_support() &&
-	       !acpi_video_verify_backlight_support();
-}
-
 static u32 asle_set_backlight(struct drm_device *dev, u32 bclp)
 {
 	struct drm_i915_private *dev_priv = dev->dev_private;
@@ -414,7 +404,7 @@ static u32 asle_set_backlight(struct drm_device *dev, u32 bclp)
 
 	DRM_DEBUG_DRIVER("bclp = 0x%08x\n", bclp);
 
-	if (should_ignore_backlight_request()) {
+	if (acpi_video_get_backlight_type() == acpi_backlight_native) {
 		DRM_DEBUG_KMS("opregion backlight request ignored\n");
 		return 0;
 	}