drm/i915: Enable ASLE if present

The changes to opregion initialisation order meant that the ASLE setup
code might not be run at the correct time. Ensure that the interrupts are
set up.

Signed-off-by: Matthew Garrett <[e-mail]>
Signed-off-by: Eric Anholt <[e-mail]>

drivers/gpu/drm/i915/i915_opregion.c

···
 	if (mboxes & MBOX_ASLE) {
 		DRM_DEBUG("ASLE supported\n");
 		opregion->asle = base + OPREGION_ASLE_OFFSET;
+		opregion_enable_asle(dev);
 	}
 
 	if (!resume)