pinctrl: nsp-gpio: fix non-static functions

Fixup warnings from functions that are not exported and
therefore should be marked static. Fixes:

drivers/pinctrl/bcm/pinctrl-nsp-gpio.c:461:5:
  warning: symbol 'nsp_pin_config_group_get' was not declared.
  Should it be static?
drivers/pinctrl/bcm/pinctrl-nsp-gpio.c:467:5:
  warning: symbol 'nsp_pin_config_group_set' was not declared.
  Should it be static?
Signed-off-by: Ben Dooks <ben.dooks@codethink.co.uk>
Acked-by: Ray Jui <ray.jui@broadcom.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>

drivers/pinctrl/bcm/pinctrl-nsp-gpio.c

@@ -458,13 +458,15 @@ static int nsp_gpio_get_strength(struct nsp_gpio *chip, unsigned gpio,
 	return 0;
 }
 
-int nsp_pin_config_group_get(struct pinctrl_dev *pctldev, unsigned selector,
+static int nsp_pin_config_group_get(struct pinctrl_dev *pctldev,
+				    unsigned selector,
 			     unsigned long *config)
 {
 	return 0;
 }
 
-int nsp_pin_config_group_set(struct pinctrl_dev *pctldev, unsigned selector,
+static int nsp_pin_config_group_set(struct pinctrl_dev *pctldev,
+				    unsigned selector,
 			     unsigned long *configs, unsigned num_configs)
 {
 	return 0;