rtc: rx8010: switch to using the preferred i2c API

We should generally use probe_new instead of probe when registering i2c
drivers. Convert rx8010 to using it.

Signed-off-by: Bartosz Golaszewski <bgolaszewski@baylibre.com>
Signed-off-by: Alexandre Belloni <alexandre.belloni@bootlin.com>
Link: https://lore.kernel.org/r/20200914154601.32245-13-brgl@bgdev.pl