genirq: Add irq disabled flag to irq_data state

Some irq_chip implementation require to know the disabled state of the
interrupt in certain callbacks. Add a state flag and accessor to
irq_data.

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

kernel/irq/irqdesc.c

@@ -80,6 +80,7 @@ static void desc_set_defaults(unsigned int irq, struct irq_desc *desc, int node)
 	desc->irq_data.handler_data = NULL;
 	desc->irq_data.msi_desc = NULL;
 	irq_settings_clr_and_set(desc, ~0, _IRQ_DEFAULT_INIT_FLAGS);
+	irqd_set(&desc->irq_data, IRQD_IRQ_DISABLED);
 	desc->istate = IRQS_DISABLED;
 	desc->handle_irq = handle_bad_irq;
 	desc->depth = 1;