fbdev: mb862xx: Fix check of return value from irq_of_parse_and_map()

NO_IRQ is used to check the return of irq_of_parse_and_map().
On some architecture NO_IRQ is 0, on other architectures it is -1.
irq_of_parse_and_map() returns 0 on error, independent of NO_IRQ.
So use 0 instead of using NO_IRQ.

Signed-off-by: Christophe Leroy <[e-mail]>
Signed-off-by: Helge Deller <[e-mail]>

drivers/video/fbdev/mb862xx/mb862xxfbdrv.c

···
 	par->dev = dev;
 
 	par->irq = irq_of_parse_and_map(np, 0);
-	if (par->irq == NO_IRQ) {
+	if (!par->irq) {
 		dev_err(dev, "failed to map irq\n");
 		ret = -ENODEV;
 		goto fbrel;