drm/i915: Unregister ACPI video driver when exiting

The i915 DRM triggers registration of the ACPI video driver on load. It
should unregister it at unload in order to avoid generating backtraces on
being reloaded.

Signed-off-by: Matthew Garrett <mjg@redhat.com>
Signed-off-by: Eric Anholt <eric@anholt.net>
diff --git a/drivers/gpu/drm/i915/i915_drv.c b/drivers/gpu/drm/i915/i915_drv.c
index 6503e22..98560e1 100644
--- a/drivers/gpu/drm/i915/i915_drv.c
+++ b/drivers/gpu/drm/i915/i915_drv.c
@@ -77,7 +77,7 @@
 		drm_irq_uninstall(dev);
 	}
 
-	intel_opregion_free(dev);
+	intel_opregion_free(dev, 1);
 
 	if (state.event == PM_EVENT_SUSPEND) {
 		/* Shut down the device */