In order for the RC6 autoenable worker to take any action, RC6 first
must be disabled. Upon resume or reset, the sw state may be stale and so
we require a forced restore.

Fixes: b7137e0c ("drm/i915: Defer enabling rc6 til after we submit...")
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Cc: Mika Kuoppala <mika.kuoppala@intel.com>
Cc: Sagar Arun Kamble <sagar.a.kamble@intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/20160824092701.19178-1-chris@chris-wilson.co.ukReviewed-by: Mika Kuoppala <mika.kuoppala@intel.com>