Revert "gpio: pxa: Make irq_chip immutable"

This reverts commit 20117cf426b6 ("gpio: pxa: Make irq_chip immutableas")
as it caused a regression on samsung coreprimevelte and we've not been
able to fix it so far.

Cc: [e-mail] # v6.16
Fixes: 20117cf426b6 ("gpio: pxa: Make irq_chip immutableas")
Reported-by: Duje Mihanović <[e-mail]>
Closes: https://lore.kernel.org/all/3367665.aeNJFYEL58@radijator/
Tested-by: Duje Mihanović <[e-mail]>
Link: https://lore.kernel.org/r/[e-mail]
Signed-off-by: Bartosz Golaszewski <[e-mail]>

drivers/gpio/gpio-pxa.c

···
 	gfer = readl_relaxed(base + GFER_OFFSET) & ~GPIO_bit(gpio);
 	writel_relaxed(grer, base + GRER_OFFSET);
 	writel_relaxed(gfer, base + GFER_OFFSET);
-
-	gpiochip_disable_irq(&pchip->chip, gpio);
 }
 
 static int pxa_gpio_set_wake(struct irq_data *d, unsigned int on)
···
 	unsigned int gpio = irqd_to_hwirq(d);
 	struct pxa_gpio_bank *c = gpio_to_pxabank(&pchip->chip, gpio);
 
-	gpiochip_enable_irq(&pchip->chip, gpio);
-
 	c->irq_mask |= GPIO_bit(gpio);
 	update_edge_detect(c);
 }
 
-static const struct irq_chip pxa_muxed_gpio_chip = {
+static struct irq_chip pxa_muxed_gpio_chip = {
 	.name		= "GPIO",
 	.irq_ack	= pxa_ack_muxed_gpio,
 	.irq_mask	= pxa_mask_muxed_gpio,
 	.irq_unmask	= pxa_unmask_muxed_gpio,
 	.irq_set_type	= pxa_gpio_irq_type,
 	.irq_set_wake	= pxa_gpio_set_wake,
-	.flags = IRQCHIP_IMMUTABLE,
-	GPIOCHIP_IRQ_RESOURCE_HELPERS,
 };
 
 static int pxa_gpio_nums(struct platform_device *pdev)