pinctrl: rockchip: fix pull setting error for rk3399

This patch fixes the pinctrl pull bias setting, since the pull up/down
setting is the contrary for gpio0(just the gpio0a and gpio0b) and
gpio2(just the gpio2c and gpio2d).

From the TRM said, the gpio0a pull polarity setting:
gpio0a_p
GPIO0A PE/PS programmation section, every
GPIO bit corresponding to 2bits[PS:PE]
2'b00: Z(Normal operation);
2'b11: weak 1(pull-up);
2'b01: weak 0(pull-down);
2'b10: Z(Normal operation);

Then, the other gpios setting as the following:
gpio1a_p (e.g.: gpio1, gpio2a, gpio2b, gpio3...)
GPIO1A PU/PD programmation section, every
GPIO bit corresponding to 2bits
2'b00: Z(Normal operation);
2'b01: weak 1(pull-up);
2'b10: weak 0(pull-down);
2'b11: Z(Normal operation);

For example,(rk3399evb board)
sdmmc_cd --->gpio0_a7
localhost / # io -r -4 0xff320040
ff320040: 00004d5f
In general,the value should be 0x0000cd5f since the pin has been set
in the dts.

Signed-off-by: David Wu <david.wu@rock-chips.com>
Signed-off-by: Caesar Wang <wxt@rock-chips.com>
Cc: linux-gpio@vger.kernel.org
Reviewed-by: Douglas Anderson <dianders@chromium.org>
Reviewed-by: Heiko Stuebner <heiko@sntech.de>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>