m68k: gpio: switch to gpiochip_add_data()

We're planning to remove the gpiochip_add() function to swith
to gpiochip_add_data() with NULL for data argument.

Cc: Geert Uytterhoeven <geert@linux-m68k.org>
Acked-by: Greg Ungerer <gerg@uclinux.org>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>

arch/m68k/coldfire/gpio.c

@@ -178,7 +178,7 @@ static struct gpio_chip mcfgpio_chip = {
 
 static int __init mcfgpio_sysinit(void)
 {
-	gpiochip_add(&mcfgpio_chip);
+	gpiochip_add_data(&mcfgpio_chip, NULL);
 	return subsys_system_register(&mcfgpio_subsys, NULL);
 }