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-aspeed.c b/drivers/gpio/gpio-aspeed.c
index 00dc1c0..2bfce0a 100644
--- a/drivers/gpio/gpio-aspeed.c
+++ b/drivers/gpio/gpio-aspeed.c
@@ -469,7 +469,7 @@
 		reg = ioread32(bank_irq_reg(data, bank, GPIO_IRQ_STATUS));
 
 		for_each_set_bit(p, &reg, 32) {
-			girq = irq_find_mapping(gc->irqdomain, i * 32 + p);
+			girq = irq_find_mapping(gc->irq.domain, i * 32 + p);
 			generic_handle_irq(girq);
 		}