Change todr_chip_handle::cookie -> todr_chip_handle::todr_dev, and
make it a device_t. Upcoming functional changes will require the
device_t associated with a TODR device.

Change todr_chip_handle::bus_cookie -> todr_chip_handle::todr_devaux.
Nothing was using the old field, but I decided to keep it around just
in cause something needs it in the future.

And with these largely mechanical yet semantically meaningful changes,
thus spake the Oracle: "Welcome to NetBSD 11.99.2."

Remove unnecessary NULL-initialization of TODR handle fields.

branches: 1.1.4; 1.1.12;
Add support SoC CL PS-711x.