drm/i915/opregion: remove unnecessary ifdefs on CONFIG_ACPI

The whole file is ignored on CONFIG_ACPI=n.

Reviewed-by: Ander Conselvan de Oliveira <conselvan2@gmail.com>
Signed-off-by: Jani Nikula <jani.nikula@intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/1460127589-8357-1-git-send-email-jani.nikula@intel.com
1 file changed