drm/i915: Allocate connector state together with the connectors

Connector states were being allocated in intel_setup_outputs() in loop
over all connectors. That meant hot-added connectors would have a NULL
state. Since the change to use a struct drm_atomic_state for the legacy
modeset, connector states are necessary for the i915 driver to function
properly, so that would lead to oopses.

Broken by

commit 944b0c7657
Author: Ander Conselvan de Oliveira <ander.conselvan.de.oliveira@intel.com>
Date:   Fri Mar 20 16:18:07 2015 +0200

    drm/i915: Copy the staged connector config to the legacy atomic state

v2: Fix test for intel_connector_init() success in lvds and sdvo (PRTS)

Signed-off-by: Ander Conselvan de Oliveira <ander.conselvan.de.oliveira@intel.com>
Reported-and-tested-by: Nicolas Kalkhof <nkalkhof@web.de>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Signed-off-by: Jani Nikula <jani.nikula@intel.com>

drivers/gpu/drm/i915/intel_hdmi.c

@@ -1750,7 +1750,7 @@ void intel_hdmi_init(struct drm_device *dev, int hdmi_reg, enum port port)
 	if (!intel_dig_port)
 		return;
 
-	intel_connector = kzalloc(sizeof(*intel_connector), GFP_KERNEL);
+	intel_connector = intel_connector_alloc();
 	if (!intel_connector) {
 		kfree(intel_dig_port);
 		return;