ARM: irq migration: force migration off CPU going down

The force argument to irq_set_affinity really should be 'true' as
moving IRQs off a CPU which is going down isn't optional.
Acked-by: NThomas Gleixner <tglx@linutronix.de>
Signed-off-by: NRussell King <rmk+kernel@arm.linux.org.uk>

arch/arm/kernel/irq.c

@@ -185,7 +185,7 @@ static void route_irq(struct irq_desc *desc, unsigned int irq, unsigned int cpu)
 
 	raw_spin_lock_irq(&desc->lock);
 	desc->irq_data.chip->irq_set_affinity(&desc->irq_data,
-					      cpumask_of(cpu), false);
+					      cpumask_of(cpu), true);
 	raw_spin_unlock_irq(&desc->lock);
 }