the wrong variable checked after request_irq()

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Acked-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

arch/powerpc/platforms/pseries/setup.c

@@ -176,7 +176,7 @@ static void __init pseries_mpic_init_IRQ(void)
 		return;
 
 	cascade_irq = irq_of_parse_and_map(cascade, 0);
-	if (cascade == NO_IRQ) {
+	if (cascade_irq == NO_IRQ) {
 		printk(KERN_ERR "mpic: failed to map cascade interrupt");
 		return;
 	}