gpio: regmap: Move optional assignments down in the code

Move optional assignments down in the code, so they may use some values
from the (updated) struct gpio_chip later on.

Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Reviewed-by: Michael Walle <mwalle@kernel.org>
Reviewed-by: Linus Walleij <linus.walleij@linaro.org>
Tested-by: Mathieu Dubois-Briand <mathieu.dubois-briand@bootlin.com>
Reviewed-by: Mathieu Dubois-Briand <mathieu.dubois-briand@bootlin.com>
Link: https://lore.kernel.org/r/20250213195621.3133406-5-andriy.shevchenko@linux.intel.com


Signed-off-by: Bartosz Golaszewski <bartosz.golaszewski@linaro.org>