ACPI / gpio: make acpi_gpiochip_parse_own_gpio static

Fixes the following sparse warning:

drivers/gpio/gpiolib-acpi.c:863:18: warning:
 symbol 'acpi_gpiochip_parse_own_gpio' was not declared. Should it be static?

Signed-off-by: Wei Yongjun <weiyongjun1@huawei.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>

drivers/gpio/gpiolib-acpi.c

@@ -857,9 +857,9 @@ static void acpi_gpiochip_free_regions(struct acpi_gpio_chip *achip)
 	}
 }
 
-struct gpio_desc *acpi_gpiochip_parse_own_gpio(struct acpi_gpio_chip *achip,
-	struct fwnode_handle *fwnode, const char **name, unsigned int *lflags,
-	unsigned int *dflags)
+static struct gpio_desc *acpi_gpiochip_parse_own_gpio(
+	struct acpi_gpio_chip *achip, struct fwnode_handle *fwnode,
+	const char **name, unsigned int *lflags, unsigned int *dflags)
 {
 	struct gpio_chip *chip = achip->chip;
 	struct gpio_desc *desc;