gpio: zevio: make gpio_chip const

Make this const as it is only used as a copy operation.
Done using Coccinelle.
Signed-off-by: Bhumika Goyal <bhumirks@gmail.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>

drivers/gpio/gpio-zevio.c

@@ -156,7 +156,7 @@ static int zevio_gpio_to_irq(struct gpio_chip *chip, unsigned pin)
 	return -ENXIO;
 }
 
-static struct gpio_chip zevio_gpio_chip = {
+static const struct gpio_chip zevio_gpio_chip = {
 	.direction_input	= zevio_gpio_direction_input,
 	.direction_output	= zevio_gpio_direction_output,
 	.set			= zevio_gpio_set,