rtc: m48t86: add DT support for m48t86

Add OF ID match table.

Acked-by: Arnd Bergmann <arnd@arndb.de>
Reviewed-by: Linus Walleij <linus.walleij@linaro.org>
Link: https://lore.kernel.org/lkml/20230601054549.10843-12-nikita.shubin@maquefel.me/


Signed-off-by: Nikita Shubin <nikita.shubin@maquefel.me>
Link: https://lore.kernel.org/r/20230823-m48t86_device_tree-v2-2-21ff275f949d@maquefel.me


Signed-off-by: Alexandre Belloni <alexandre.belloni@bootlin.com>