drm/i915/opregion: Cleanup opregion after errors during driver loading

Clean up the opregion state if something fails after
intel_opregion_setup() is called.

Reviewed-by: Jani Nikula <jani.nikula@intel.com>
Signed-off-by: Imre Deak <imre.deak@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20230308162503.3219200-2-imre.deak@intel.com