drm/i915: Set connector_state->connector using the helper.

BugLink: http://bugs.launchpad.net/bugs/1540390

The atomic helper sets connector_state->connector, which the i915
code didn't. This will become a problem when we start using it.
Signed-off-by: Maarten Lankhorst <maarten.lankhorst@linux.intel.com>
Acked-by: Thierry Reding <treding@nvidia.com>
Link: http://patchwork.freedesktop.org/patch/msgid/1451908400-25147-1-git-send-email-maarten.lankhorst@linux.intel.comSigned-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
(cherry picked from commit 5350a031)
Signed-off-by: Timo Aaltonen <timo.aaltonen@canonical.com>
Signed-off-by: Andy Whitcroft <apw@canonical.com>

drivers/gpu/drm/i915/intel_display.c

@@ -6447,13 +6447,11 @@ static void intel_connector_check_state(struct intel_connector *connector)
 
 int intel_connector_init(struct intel_connector *connector)
 {
-	struct drm_connector_state *connector_state;
+	drm_atomic_helper_connector_reset(&connector->base);
 
-	connector_state = kzalloc(sizeof *connector_state, GFP_KERNEL);
-	if (!connector_state)
+	if (!connector->base.state)
 		return -ENOMEM;
 
-	connector->base.state = connector_state;
 	return 0;
 }