build fix: CONFIG_DRM_I915=y && CONFIG_ACPI=n

drivers/gpu/drm/i915/i915_opregion.c:340: error: implicit declaration of function ‘register_acpi_notifier’
drivers/gpu/drm/i915/i915_opregion.c:361: error: implicit declaration of function ‘unregister_acpi_notifier’

Signed-off-by: Len Brown <len.brown@intel.com>
Signed-off-by: Eric Anholt <eric@anholt.net>
Signed-off-by: Dave Airlie <airlied@redhat.com>
2 files changed