pinctrl: Use new GPIO_LINE_DIRECTION

Use newly added GPIO defines GPIO_LINE_DIRECTION_IN and
GPIO_LINE_DIRECTION_OUT instead of using hard-coded 1 and 0.

Main benefit is to make it easier to see which values mean IN and which
OUT. As a side effect this helps GPIO framework to change the direction
defines to something else if ever needed.

Please note that return value from get_direction call on
pinctrl-axp209 driver was changed. Previously pinctrl-axp209 might have
returned value 2 for direction INPUT.

Signed-off-by: Matti Vaittinen <matti.vaittinen@fi.rohmeurope.com>
Reported-by: kbuild test robot <lkp@intel.com>
Reviewed-by: Geert Uytterhoeven <geert+renesas@glider.be>
Acked-by: Geert Uytterhoeven <geert+renesas@glider.be>
Reviewed-by: Bjorn Andersson <bjorn.andersson@linaro.org>
Reviewed-by: Jacopo Mondi <jacopo+renesas@jmondi.org>
Link: https://lore.kernel.org/r/20200214135712.GA14557@localhost.localdomain


Signed-off-by: Linus Walleij <linus.walleij@linaro.org>