drm/i915: Attach HDR metadata property to connector

Attach HDR metadata property to connector object.

v2: Rebase

v3: Updated the property name as per updated name
while creating hdr metadata property

v4: Added platform check as suggested by Ville.
Signed-off-by: Uma Shankar <uma.shankar@intel.com>
Reviewed-by: Shashank Sharma <shashank.sharma@intel.com>
Reviewed-by: Maarten Lankhorst <maarten.lankhorst@linux.intel.com>
Signed-off-by: Maarten Lankhorst <maarten.lankhorst@linux.intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/1558109949-3309-1-git-send-email-uma.shankar@intel.com

drivers/gpu/drm/i915/intel_hdmi.c

@@ -2771,6 +2771,10 @@ intel_hdmi_add_properties(struct intel_hdmi *intel_hdmi, struct drm_connector *c
 	drm_connector_attach_content_type_property(connector);
 	connector->state->picture_aspect_ratio = HDMI_PICTURE_ASPECT_NONE;
 
+	if (INTEL_GEN(dev_priv) >= 10 || IS_GEMINILAKE(dev_priv))
+		drm_object_attach_property(&connector->base,
+			connector->dev->mode_config.hdr_output_metadata_property, 0);
+
 	if (!HAS_GMCH(dev_priv))
 		drm_connector_attach_max_bpc_property(connector, 8, 12);
 }