[media] staging: lirc_serial: Do not assume error codes returned by request_irq()

lirc_serial_probe() must fail if request_irq() returns an error, even if
it isn't EBUSY or EINVAL,
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>

drivers/staging/media/lirc/lirc_serial.c

@@ -843,18 +843,15 @@ static int __devinit lirc_serial_probe(struct platform_device *dev)
 	result = request_irq(irq, irq_handler,
 			     (share_irq ? IRQF_SHARED : 0),
 			     LIRC_DRIVER_NAME, (void *)&hardware);
-
-	switch (result) {
-	case -EBUSY:
-		printk(KERN_ERR LIRC_DRIVER_NAME ": IRQ %d busy\n", irq);
-		return -EBUSY;
-	case -EINVAL:
-		printk(KERN_ERR LIRC_DRIVER_NAME
-		       ": Bad irq number or handler\n");
-		return -EINVAL;
-	default:
-		break;
-	};
+	if (result < 0) {
+		if (result == -EBUSY)
+			printk(KERN_ERR LIRC_DRIVER_NAME ": IRQ %d busy\n",
+			       irq);
+		else if (result == -EINVAL)
+			printk(KERN_ERR LIRC_DRIVER_NAME
+			       ": Bad irq number or handler\n");
+		return result;
+	}
 
 	/* Reserve io region. */
 	/*