gpio: zevio: Add missing header

The commit 899f6a9c4364 ("gpio: zevio: Use proper headers and drop
OF_GPIO dependency") missed one header this driver depends on. Add it.

Fixes: 899f6a9c4364 ("gpio: zevio: Use proper headers and drop OF_GPIO dependency")
Reported-by: kernel test robot <lkp@intel.com>
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: Bartosz Golaszewski <bartosz.golaszewski@linaro.org>