pinctrl: sunxi: H3 requires irq_read_needs_mux

It seems that on H3, just like on A10, when GPIOs are configured as
external interrupt data registers does not contain their value.  When
value is read, GPIO function must be temporary switched to input for
reads.

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