gpio: gpiolib: set gpiochip_remove retval to void

This avoids handling gpiochip remove error in device
remove handler.

Signed-off-by: Abdoulaye Berthe <berthe.ab@gmail.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
diff --git a/include/linux/gpio/driver.h b/include/linux/gpio/driver.h
index a2de58ff..560bf7f 100644
--- a/include/linux/gpio/driver.h
+++ b/include/linux/gpio/driver.h
@@ -141,7 +141,7 @@
 
 /* add/remove chips */
 extern int gpiochip_add(struct gpio_chip *chip);
-extern int gpiochip_remove(struct gpio_chip *chip);
+extern void gpiochip_remove(struct gpio_chip *chip);
 extern struct gpio_chip *gpiochip_find(void *data,
 			      int (*match)(struct gpio_chip *chip, void *data));