There are two bits in the PADCFG0 register to configure direction, one per
TX/RX buffers.

For now we wrongly assume that the GPIO is always requested before it is being
used, which is not true when the GPIO is used through irqchip. In this case the
GPIO is never requested and we never enable RX buffer for it.

Fix this by setting both bits accordingly.
Reported-by: Jarkko Nikula <jarkko.nikula@linux.intel.com>
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>