gpio: mpc8xxx: Fix IRQ check in mpc8xxx_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: 76c47d14 ("gpio: mpc8xxx: Add ACPI support") Signed-off-by: Miaoqian Lin <linmq006@gmail.com> Reviewed-by: Linus Walleij <linus.walleij@linaro.org> Signed-off-by: Bartosz Golaszewski <brgl@bgdev.pl>