gpio: idt3243x: Fix IRQ check in idt_gpio_probe

platform_get_irq() returns negative error number instead 0 on failure.
And the doc of platform_get_irq() provides a usage example:

    int irq = platform_get_irq(pdev, 0);
    if (irq < 0)
        return irq;

Fix the check of return value to catch errors correctly.

Fixes: 4195926aed ("gpio: Add support for IDT 79RC3243x GPIO controller")
Signed-off-by: Miaoqian Lin <linmq006@gmail.com>
Reviewed-by: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Bartosz Golaszewski <brgl@bgdev.pl>

drivers/gpio/gpio-idt3243x.c

@@ -164,8 +164,8 @@ static int idt_gpio_probe(struct platform_device *pdev)
 			return PTR_ERR(ctrl->pic);
 
 		parent_irq = platform_get_irq(pdev, 0);
-		if (!parent_irq)
-			return -EINVAL;
+		if (parent_irq < 0)
+			return parent_irq;
 
 		girq = &ctrl->gc.irq;
 		girq->chip = &idt_gpio_irqchip;