gpio: crystalcove: Free IRQ on error path

gpio: crystalcove: Free IRQ on error path

It appears that all, but request_irq(), calls in the driver are device managed.
In unlikely case of devm_gpiochip_add_data() failure the IRQ left requested.
Free IRQ on error path by switching to devm_request_threaded_irq() API.

Byproduct of this change is a drop of ->remove() callback completely.

Fixes: 945e72db36bd ("gpio: crystalcove: Use irqchip template")
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Link: https://lore.kernel.org/r/20200728125504.27786-2-andriy.shevchenko@linux.intel.com
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>