gpio: kempld: Be sure to clamp return value

As we want gpio_chip .get() calls to be able to return negative
error codes and propagate to drivers, we need to go over all
drivers and make sure their return values are clamped to [0,1].
We do this by using the ret = !!(val) design pattern.

Cc: Brunner Michael <Michael.Brunner@kontron.com>
Reviewed-by: Guenter Roeck <linux@roeck-us.net>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>

drivers/gpio/gpio-kempld.c

@@ -69,7 +69,7 @@ static int kempld_gpio_get(struct gpio_chip *chip, unsigned offset)
 		= container_of(chip, struct kempld_gpio_data, chip);
 	struct kempld_device_data *pld = gpio->pld;
 
-	return kempld_gpio_get_bit(pld, KEMPLD_GPIO_LVL_NUM(offset), offset);
+	return !!kempld_gpio_get_bit(pld, KEMPLD_GPIO_LVL_NUM(offset), offset);
 }
 
 static void kempld_gpio_set(struct gpio_chip *chip, unsigned offset, int value)