gpio: pxa: use devm_irq_alloc_descs()

This driver never frees the interrupt descriptors it allocates. Fix
it by using the resource managed version of irq_alloc_descs().

Signed-off-by: Bartosz Golaszewski <[e-mail]>
Acked-by: Robert Jarzmik <[e-mail]>
Signed-off-by: Linus Walleij <[e-mail]>

drivers/gpio/gpio-pxa.c

···
 	nr_gpios = gpio_id->gpio_nums;
 	pxa_last_gpio = nr_gpios - 1;
 
-	irq_base = irq_alloc_descs(-1, 0, nr_gpios, 0);
+	irq_base = devm_irq_alloc_descs(&pdev->dev, -1, 0, nr_gpios, 0);
 	if (irq_base < 0) {
 		dev_err(&pdev->dev, "Failed to allocate IRQ numbers\n");
 		return irq_base;