genirq: Mirror IRQ_PER_CPU and IRQ_NO_BALANCING in irq_data.state

That's the right data structure to look at for arch code.

Accessor functions are provided.

	 irqd_is_per_cpu(irqdata);
	 irqd_can_balance(irqdata);

Coders who access them directly will be tracked down and slapped with
stinking trouts.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>

kernel/irq/spurious.c

@@ -68,7 +68,8 @@ static int try_one_irq(int irq, struct irq_desc *desc, bool force)
 	raw_spin_lock(&desc->lock);
 
 	/* PER_CPU and nested thread interrupts are never polled */
-	if (desc->status & (IRQ_PER_CPU | IRQ_NESTED_THREAD))
+	if (irq_settings_is_per_cpu(desc) ||
+	    (desc->status & IRQ_NESTED_THREAD))
 		goto out;
 
 	/*