drm/i915: Use correct iterator macro

for_each_connector_in_state will be removed, so use the right state
here.

Signed-off-by: Maarten Lankhorst <maarten.lankhorst@linux.intel.com>
Cc: Daniel Vetter <daniel.vetter@intel.com>
Cc: Jani Nikula <jani.nikula@linux.intel.com>
Cc: intel-gfx@lists.freedesktop.org
Link: http://patchwork.freedesktop.org/patch/msgid/20170712081344.25495-7-maarten.lankhorst@linux.intel.com


Reviewed-by: Daniel Vetter <daniel.vetter@ffwll.ch>