pinctrl: rockchip: Add rk3128 pinctrl support

There are 3 IP blocks pin routes need to be switched, that are
emmc-cmd, spi, i2s. And there are some pins need to be recalced,
which are gpio2c4~gpio2c7 and gpio2d0.

Signed-off-by: David Wu <david.wu@rock-chips.com>
Reviewed-by: Heiko Stuebner <heiko@sntech.de>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>