MAINTAINERS: Appoint Marc Zyngier as irqchips co-maintainer

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Acked-by: Jason Cooper <jason@lakedaemon.net>
Cc: Marc Zyngier <marc.zyngier@arm.com>

MAINTAINERS

@@ -5600,6 +5600,7 @@ F:	kernel/irq/
 IRQCHIP DRIVERS
 M:	Thomas Gleixner <tglx@linutronix.de>
 M:	Jason Cooper <jason@lakedaemon.net>
+M:	Marc Zyngier <marc.zyngier@arm.com>
 L:	linux-kernel@vger.kernel.org
 S:	Maintained
 T:	git git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip.git irq/core