auxdisplay: ht16k33: Make use of device properties

The device property API allows drivers to gather device resources from
different sources, such as ACPI, and lift the dependency on Device Tree.
Convert the driver to unleash the power of the device property API.

Suggested-by: Marek Behún <kabel@kernel.org>
Signed-off-by: Geert Uytterhoeven <geert@linux-m68k.org>
Reviewed-by: Andy Shevchenko <andy.shevchenko@gmail.com>
Acked-by: Robin van der Gracht <robin@protonic.nl>
Signed-off-by: Miguel Ojeda <ojeda@kernel.org>