gpio: ucb1400: 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.
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>

drivers/gpio/gpio-ucb1400.c

@@ -33,7 +33,7 @@ static int ucb1400_gpio_get(struct gpio_chip *gc, unsigned off)
 {
 	struct ucb1400_gpio *gpio;
 	gpio = container_of(gc, struct ucb1400_gpio, gc);
-	return ucb1400_gpio_get_value(gpio->ac97, off);
+	return !!ucb1400_gpio_get_value(gpio->ac97, off);
 }
 
 static void ucb1400_gpio_set(struct gpio_chip *gc, unsigned off, int val)