dmaengine: axi-dmac: Propagate errors from platform_get_irq()

Propagate errors returned by platform_get_irq() to the driver core. This
will enable proper probe deferring for the driver in case the IRQ provider
has not been registered yet.

Signed-off-by: Lars-Peter Clausen <lars@metafoo.de>
Signed-off-by: Vinod Koul <vinod.koul@intel.com>
diff --git a/drivers/dma/dma-axi-dmac.c b/drivers/dma/dma-axi-dmac.c
index 8b0de8c..0e0dfc0 100644
--- a/drivers/dma/dma-axi-dmac.c
+++ b/drivers/dma/dma-axi-dmac.c
@@ -579,7 +579,9 @@
 		return -ENOMEM;
 
 	dmac->irq = platform_get_irq(pdev, 0);
-	if (dmac->irq <= 0)
+	if (dmac->irq < 0)
+		return dmac->irq;
+	if (dmac->irq == 0)
 		return -EINVAL;
 
 	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);