usb: typec: tipd: Add cd321x struct with separate size

usb: typec: tipd: Add cd321x struct with separate size

We're about to add more fields to struct tps6598x which are only relevant
for Apple's CD321x and to ensure that we don't waste memory everywhere for
those add a separate struct for cd321x and prepare to allocate more space
inside probe.

Reviewed-by: Heikki Krogerus <heikki.krogerus@linux.intel.com>
Reviewed-by: Neal Gompa <neal@gompa.dev>
Signed-off-by: Sven Peter <sven@kernel.org>
Link: https://lore.kernel.org/r/20250914-apple-usb3-tipd-v1-5-4e99c8649024@kernel.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>