uio_pdrv_genirq: get irq through platform resource if not set otherwise

Platform devices are configured through platform resources. The interrupt
in the driver uio_pdrv_genirq is instead configured through a side channel
i.e. the platform data structure. Make it possible to use the generic
configuration scheme via platform resource.
Signed-off-by: Benedikt Spranger <b.spranger@linutronix.de>
Acked-by: Magnus Damm <damm@opensource.se>
Signed-off-by: "Hans J. Koch" <hjk@hansjkoch.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

drivers/uio/uio_pdrv_genirq.c

@@ -146,6 +146,14 @@ static int uio_pdrv_genirq_probe(struct platform_device *pdev)
 	priv->flags = 0; /* interrupt is enabled to begin with */
 	priv->pdev = pdev;
 
+	if (!uioinfo->irq) {
+		ret = platform_get_irq(pdev, 0);
+		if (ret < 0) {
+			dev_err(&pdev->dev, "failed to get IRQ\n");
+			goto bad0;
+		}
+		uioinfo->irq = ret;
+	}
 	uiomem = &uioinfo->mem[0];
 
 	for (i = 0; i < pdev->num_resources; ++i) {