It's logically better to check the IN in ->direction_input() and
_OUT in ->direction_output().

While at it, replace ternary with plain if-conditional for the sake
of consistency with mmio_74xx_dir_out().
Signed-off-by: NAndy Shevchenko <andriy.shevchenko@linux.intel.com>
Reviewed-by: NLinus Walleij <linus.walleij@linaro.org>
Signed-off-by: NBartosz Golaszewski <brgl@bgdev.pl>