arm: Move the set_handle_irq and handle_arch_irq declarations to asm/irq.h

This patch prepares the removal of <asm/mach/irq.h> include in the
GIC and VIC irqchip drivers.

Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
Tested-by: Marc Zyngier <marc.zyngier@arm.com>
Cc: Russell King <linux@arm.linux.org.uk>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Rob Herring <rob.herring@calxeda.com>
diff --git a/drivers/irqchip/irq-vic.c b/drivers/irqchip/irq-vic.c
index 3cf97aa..e38cb00 100644
--- a/drivers/irqchip/irq-vic.c
+++ b/drivers/irqchip/irq-vic.c
@@ -33,7 +33,7 @@
 #include <linux/irqchip/arm-vic.h>
 
 #include <asm/exception.h>
-#include <asm/mach/irq.h>
+#include <asm/irq.h>
 
 #include "irqchip.h"