gpio: max77620: get gpio value based on direction

Gpio direction is determined by DIRx bit of GPIO
configuration register, return max77620 gpio value
based on direction in or out.

Signed-off-by: Venkat Reddy Talla <vreddytalla@nvidia.com>
Reviewed-by: Alexandre Courbot <acourbot@nvidia.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>