fbdev: omapfb: Fix tests for platform_get_irq() failure

The platform_get_irq() returns negative error codes.  It can't actually
return zero.
Signed-off-by: Yu Zhe <yuzhe@nfschina.com>
Signed-off-by: Helge Deller <deller@gmx.de>

drivers/video/fbdev/omap/omapfb_main.c

@@ -1642,14 +1642,14 @@ static int omapfb_do_probe(struct platform_device *pdev,
 		goto cleanup;
 	}
 	fbdev->int_irq = platform_get_irq(pdev, 0);
-	if (!fbdev->int_irq) {
+	if (fbdev->int_irq < 0) {
 		dev_err(&pdev->dev, "unable to get irq\n");
 		r = ENXIO;
 		goto cleanup;
 	}
 
 	fbdev->ext_irq = platform_get_irq(pdev, 1);
-	if (!fbdev->ext_irq) {
+	if (fbdev->ext_irq < 0) {
 		dev_err(&pdev->dev, "unable to get irq\n");
 		r = ENXIO;
 		goto cleanup;