gpio: merrifield: Fix build err without CONFIG_ACPI

When building CONFIG_ACPI is not set
gcc warn this:

drivers/gpio/gpio-merrifield.c: In function mrfld_gpio_get_pinctrl_dev_name:
drivers/gpio/gpio-merrifield.c:388:19: error: dereferencing pointer to incomplete type struct acpi_device
   put_device(&adev->dev);
                   ^~

Reported-by: Hulk Robot <hulkci@huawei.com>
Fixes: d00d2109 ("gpio: merrifield: Convert to use acpi_dev_get_first_match_dev()")
Suggested-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: YueHaibing <yuehaibing@huawei.com>
Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Acked-by: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>