drm/i915: Use new atomic iterator macros in ddi

Use for_each_new_connector_in_state instead of for_each_connector_in_state.
Also make the function static, it's only used inside intel_ddi.c

Signed-off-by: Maarten Lankhorst <maarten.lankhorst@linux.intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/1489071125-917-2-git-send-email-maarten.lankhorst@linux.intel.com


Reviewed-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Reviewed-by: Ville Syrjälä <ville.syrjala@linux.intel.com>