Since Linux gpio framework return 0 for output, 1 for input.
But HW use 0 stands for input, and 1 stands for output.
So use negative to correct it.

And gpio_chip.get is used to get input value, no need to get
output value, so removing it.
Signed-off-by: NHongzhou Yang <hongzhou.yang@mediatek.com>
Signed-off-by: NLinus Walleij <linus.walleij@linaro.org>