pinctrl: mtk: Fix low level output voltage issue

pinctrl: mtk: Fix low level output voltage issue

This patch is used to fix low level output voltage issue.
A pin is changed from input pull-up to output high.
The Dout value of the pin is default as 0.
If we change the direction of the pin before the dout value of the pin,
It maybe produce a low level output voltage between "input pull-up" and
"output high".

Signed-off-by: Zhiyong Tao <zhiyong.tao@mediatek.com>
Link: https://lore.kernel.org/r/20201120093058.7248-2-zhiyong.tao@mediatek.com
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>