gpio: em: 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: Magnus Damm <damm@opensource.se>
Acked-by: Geert Uytterhoeven <geert+renesas@glider.be>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>

drivers/gpio/gpio-em.c

@@ -203,7 +203,7 @@ static int em_gio_direction_input(struct gpio_chip *chip, unsigned offset)
 
 static int em_gio_get(struct gpio_chip *chip, unsigned offset)
 {
-	return (int)(em_gio_read(gpio_to_priv(chip), GIO_I) & BIT(offset));
+	return !!(em_gio_read(gpio_to_priv(chip), GIO_I) & BIT(offset));
 }
 
 static void __em_gio_set(struct gpio_chip *chip, unsigned int reg,