gpio: 74xx-mmio: Check MMIO_74XX_DIR_IN flag in mmio_74xx_dir_in()

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: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Reviewed-by: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Bartosz Golaszewski <brgl@bgdev.pl>

drivers/gpio/gpio-74xx-mmio.c

@@ -88,7 +88,10 @@ static int mmio_74xx_dir_in(struct gpio_chip *gc, unsigned int gpio)
 {
 	struct mmio_74xx_gpio_priv *priv = gpiochip_get_data(gc);
 
-	return (priv->flags & MMIO_74XX_DIR_OUT) ? -ENOTSUPP : 0;
+	if (priv->flags & MMIO_74XX_DIR_IN)
+		return 0;
+
+	return -ENOTSUPP;
 }
 
 static int mmio_74xx_dir_out(struct gpio_chip *gc, unsigned int gpio, int val)