Input: gpio_keys_polled - simplify with dev_err_probe()

Input: gpio_keys_polled - simplify with dev_err_probe()

Common pattern of handling deferred probe can be simplified with
dev_err_probe().  Less code and also it prints the error value.

Signed-off-by: Krzysztof Kozlowski <krzysztof.kozlowski@linaro.org>
Reviewed-by: Hans de Goede <hdegoede@redhat.com>
Reviewed-by: Andy Shevchenko <andy.shevchenko@gmail.com>
Reviewed-by: Linus Walleij <linus.walleij@linaro.org>
Link: https://lore.kernel.org/r/20230625162817.100397-2-krzysztof.kozlowski@linaro.org
Signed-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>