gpio: Move irqdomain into struct gpio_irq_chip

In order to consolidate the multiple ways to associate an IRQ chip with
a GPIO chip, move more fields into the new struct gpio_irq_chip.

Signed-off-by: Thierry Reding <treding@nvidia.com>
Acked-by: Grygorii Strashko <grygorii.strashko@ti.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
diff --git a/drivers/gpio/gpio-wcove.c b/drivers/gpio/gpio-wcove.c
index 85341ea..dde7c6a 100644
--- a/drivers/gpio/gpio-wcove.c
+++ b/drivers/gpio/gpio-wcove.c
@@ -350,7 +350,7 @@ static irqreturn_t wcove_gpio_irq_handler(int irq, void *data)
 			offset = (gpio > GROUP0_NR_IRQS) ? 1 : 0;
 			mask = (offset == 1) ? BIT(gpio - GROUP0_NR_IRQS) :
 								BIT(gpio);
-			virq = irq_find_mapping(wg->chip.irqdomain, gpio);
+			virq = irq_find_mapping(wg->chip.irq.domain, gpio);
 			handle_nested_irq(virq);
 			regmap_update_bits(wg->regmap, IRQ_STATUS_BASE + offset,
 								mask, mask);