gpiolib-of: staticize the pin range calls

Commit 69e1601bca88809dc118abd1becb02c15a02ec71
"gpiolib: provide provision to register pin ranges"

Declared the of_gpiochip_[add|remove]_pin_range() global
while they should be static as they are only ever used in
this file. Let's convert them to static.
Reviewed-by: Stephen Warren <swarren@nvidia.com>
Reviewed-by: Viresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>

drivers/gpio/gpiolib-of.c

@@ -218,7 +218,7 @@ int of_mm_gpiochip_add(struct device_node *np,
 EXPORT_SYMBOL(of_mm_gpiochip_add);
 
 #ifdef CONFIG_PINCTRL
-void of_gpiochip_add_pin_range(struct gpio_chip *chip)
+static void of_gpiochip_add_pin_range(struct gpio_chip *chip)
 {
 	struct device_node *np = chip->of_node;
 	struct gpio_pin_range *pin_range;
@@ -254,7 +254,7 @@ void of_gpiochip_add_pin_range(struct gpio_chip *chip)
 	} while (index++);
 }
 
-void of_gpiochip_remove_pin_range(struct gpio_chip *chip)
+static void of_gpiochip_remove_pin_range(struct gpio_chip *chip)
 {
 	struct gpio_pin_range *pin_range, *tmp;
 
@@ -265,8 +265,8 @@ void of_gpiochip_remove_pin_range(struct gpio_chip *chip)
 	}
 }
 #else
-void of_gpiochip_add_pin_range(struct gpio_chip *chip) {}
-void of_gpiochip_remove_pin_range(struct gpio_chip *chip) {}
+static void of_gpiochip_add_pin_range(struct gpio_chip *chip) {}
+static void of_gpiochip_remove_pin_range(struct gpio_chip *chip) {}
 #endif
 
 void of_gpiochip_add(struct gpio_chip *chip)