gpiolib: devres: shrink devm_gpiochip_add_data_with_key()

If all we want to manage is a single pointer, there's no need to
manually allocate and add a new devres. We can simply use
devm_add_action_or_reset() and shrink the code by a good bit.

Signed-off-by: Bartosz Golaszewski <bgolaszewski@baylibre.com>
Reviewed-by: Linus Walleij <linus.walleij@linaro.org>