genirq: export irq_chip_set_wake_parent symbol

Export the irq_chip_set_wake_parent symbol so that drivers with
hierarchical IRQ chips can be built as a module.
Signed-off-by: Brian Masney <masneyb@onstation.org>
Reported-by: Mark Brown <broonie@kernel.org>
Acked-by: Marc Zyngier <marc.zyngier@arm.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>

kernel/irq/chip.c

@@ -1381,6 +1381,7 @@ int irq_chip_set_wake_parent(struct irq_data *data, unsigned int on)
 
 	return -ENOSYS;
 }
+EXPORT_SYMBOL_GPL(irq_chip_set_wake_parent);
 #endif
 
 /**