irqchip: GICv3: Convert to domain hierarchy

In order to start supporting stacked domains, convert the GICv3
code base to the new domain hierarchy framework, which mostly
amounts to supporting the new alloc/free callbacks.

Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
Link: https://lkml.kernel.org/r/1416839720-18400-3-git-send-email-marc.zyngier@arm.com
Signed-off-by: Jason Cooper <jason@lakedaemon.net>
diff --git a/drivers/irqchip/Kconfig b/drivers/irqchip/Kconfig
index b21f12f..4631685 100644
--- a/drivers/irqchip/Kconfig
+++ b/drivers/irqchip/Kconfig
@@ -14,6 +14,7 @@
 	bool
 	select IRQ_DOMAIN
 	select MULTI_IRQ_HANDLER
+	select IRQ_DOMAIN_HIERARCHY
 
 config ARM_NVIC
 	bool