scsi: sni_53c710: Add IRQ check

The driver neglects to check the result of platform_get_irq()'s call and
blithely passes the negative error codes to request_irq() (which takes
*unsigned* IRQ #s), causing it to fail with -EINVAL (overridden by -ENODEV
further below).  Stop calling request_irq() with the invalid IRQ #s.

Link: https://lore.kernel.org/r/8f4b8fa5-8251-b977-70a1-9099bcb4bb17@omprussia.ru
Fixes: c27d85f3 ("[SCSI] SNI RM 53c710 driver")
Signed-off-by: Sergey Shtylyov <s.shtylyov@omprussia.ru>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>

drivers/scsi/sni_53c710.c

@@ -58,6 +58,7 @@ static int snirm710_probe(struct platform_device *dev)
 	struct NCR_700_Host_Parameters *hostdata;
 	struct Scsi_Host *host;
 	struct  resource *res;
+	int rc;
 
 	res = platform_get_resource(dev, IORESOURCE_MEM, 0);
 	if (!res)
@@ -83,7 +84,9 @@ static int snirm710_probe(struct platform_device *dev)
 		goto out_kfree;
 	host->this_id = 7;
 	host->base = base;
-	host->irq = platform_get_irq(dev, 0);
+	host->irq = rc = platform_get_irq(dev, 0);
+	if (rc < 0)
+		goto out_put_host;
 	if(request_irq(host->irq, NCR_700_intr, IRQF_SHARED, "snirm710", host)) {
 		printk(KERN_ERR "snirm710: request_irq failed!\n");
 		goto out_put_host;