pata_of_platform: Don't use NO_IRQ

Drivers should not use NO_IRQ; moreover, some architectures don't
have it nowadays. '0' is the 'no irq' case.

Signed-off-by: Anton Vorontsov <cbouatmailru@gmail.com>
Acked-by: Alan Cox <alan@linux.intel.com>
Signed-off-by: Jeff Garzik <jgarzik@redhat.com>

drivers/ata/pata_of_platform.c

diff --git a/drivers/ata/pata_of_platform.c b/drivers/ata/pata_of_platform.c
index a72ab0d..2a472c5 100644
--- a/drivers/ata/pata_of_platform.c
+++ b/drivers/ata/pata_of_platform.c
@@ -52,7 +52,7 @@
 	}
 
 	ret = of_irq_to_resource(dn, 0, &irq_res);
-	if (ret == NO_IRQ)
+	if (!ret)
 		irq_res.start = irq_res.end = 0;
 	else
 		irq_res.flags = 0;