gpio/gpio-ich: make ichx_gpio_check_available() return a pure boolean value

It is more readable for humans to use double-bang (!!) to convert the value
to pure boolean before it is returned.
Signed-off-by: NMika Westerberg <mika.westerberg@linux.intel.com>
Signed-off-by: NLinus Walleij <linus.walleij@linaro.org>

drivers/gpio/gpio-ich.c

@@ -130,7 +130,7 @@ static int ichx_read_bit(int reg, unsigned nr)
 
 static bool ichx_gpio_check_available(struct gpio_chip *gpio, unsigned nr)
 {
-	return ichx_priv.use_gpio & (1 << (nr / 32));
+	return !!(ichx_priv.use_gpio & (1 << (nr / 32)));
 }
 
 static int ichx_gpio_direction_input(struct gpio_chip *gpio, unsigned nr)