extcon: max14577: Properly handle regmap_irq_get_virq error

The regmap_irq_get_virq may return 0 or -EINVAL on error. Fail the probe
in both situations.

Signed-off-by: Krzysztof Kozlowski <k.kozlowski@samsung.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Chanwoo Choi <cw00.choi@samsung.com>
diff --git a/drivers/extcon/extcon-max14577.c b/drivers/extcon/extcon-max14577.c
index 4179ce1..2acf746 100644
--- a/drivers/extcon/extcon-max14577.c
+++ b/drivers/extcon/extcon-max14577.c
@@ -721,7 +721,7 @@
 		unsigned int virq = 0;
 
 		virq = regmap_irq_get_virq(max14577->irq_data, muic_irq->irq);
-		if (!virq)
+		if (virq <= 0)
 			return -EINVAL;
 		muic_irq->virq = virq;