gpio: latch: store the address of pdev->dev in a helper variable

Make the code a bit more readable by using a helper variable to store
the address of pdev->dev in probe().

Reviewed-by: Linus Walleij <linus.walleij@linaro.org>
Link: https://lore.kernel.org/r/20250211120847.42437-2-brgl@bgdev.pl


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