Revert "drm/i915: Don't skip request retirement if the active list is empty"

Revert "drm/i915: Don't skip request retirement if the active list is empty"

This reverts commit f78450d63162b19d25a326df89906b835f840410.

I messed things up while applying [1] to drm-intel-fixes. Rectify.

[1] http://mid.gmane.org/1432827156-9605-1-git-send-email-ville.syrjala@linux.intel.com

Fixes: f78450d63162 ("drm/i915: Don't skip request retirement if the active list is empty")
Cc: stable@vger.kernel.org
Acked-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Signed-off-by: Jani Nikula <jani.nikula@intel.com>