pinctrl: sunxi: Add H3 R_PIO controller support

H3 has additional PIO controller similar to what we can find on A23.
It's a 12 pin port, described in H3 Datasheet rev 1.1, pages 345-350.

Signed-off-by: Krzysztof Adamski <k@japko.eu>
Acked-by: Maxime Ripard <maxime.ripard@free-electrons.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>