platform_get_irq() returns non-zero IRQ number on success,
negative error number 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: dcc21cc09e3c2 ("mfd: Add driver for Atmel Microcontroller on iPaq h3xxx")
Signed-off-by: Zheng Yongjun <zhengyongjun3@huawei.com>
---
 drivers/mfd/ipaq-micro.c | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/drivers/mfd/ipaq-micro.c b/drivers/mfd/ipaq-micro.c
index e92eeeb67a98..ac042bfd38a8 100644
--- a/drivers/mfd/ipaq-micro.c
+++ b/drivers/mfd/ipaq-micro.c
@@ -403,8 +403,8 @@ static int __init micro_probe(struct platform_device *pdev)
 	micro_reset_comm(micro);
 
 	irq = platform_get_irq(pdev, 0);
-	if (!irq)
-		return -EINVAL;
+	if (irq < 0)
+		return irq;
 	ret = devm_request_irq(&pdev->dev, irq, micro_serial_isr,
 			       IRQF_SHARED, "ipaq-micro",
 			       micro);
-- 
2.17.1