powerpc/85xx: Mark cascade irq IRQF_NO_THREAD

Cascade interrupt must run in hard interrupt context.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
diff --git a/arch/powerpc/platforms/85xx/mpc85xx_cds.c b/arch/powerpc/platforms/85xx/mpc85xx_cds.c
index 66cb8d6..7e2a4d2 100644
--- a/arch/powerpc/platforms/85xx/mpc85xx_cds.c
+++ b/arch/powerpc/platforms/85xx/mpc85xx_cds.c
@@ -177,7 +177,7 @@
 
 static struct irqaction mpc85xxcds_8259_irqaction = {
 	.handler = mpc85xx_8259_cascade_action,
-	.flags = IRQF_SHARED,
+	.flags = IRQF_SHARED | IRQF_NO_THREAD,
 	.name = "8259 cascade",
 };
 #endif /* PPC_I8259 */