platform/chrome: cros_ec_typec: Set parent of partner PD object

In order to tell what Type-C device a PD object belongs to, its parent
needs to be set. Use the Type-C partner USB PD registration wrapper
to set the parent appropriately for PD objects which are created for
connected Type-C partners.

Cc: Benson Leung <bleung@chromium.org>
Cc: Heikki Krogerus <heikki.krogerus@linux.intel.com>
Reviewed-by: Heikki Krogerus <heikki.krogerus@linux.intel.com>
Signed-off-by: Prashant Malani <pmalani@chromium.org>
Link: https://lore.kernel.org/r/20221122220538.2991775-3-pmalani@chromium.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>