irqchip: mmp: avoid use head file in a specific arch

For example, arm64 doesn't have mach/irq.h.

Signed-off-by: Neil Zhang <zhangwm@marvell.com>
Acked-by: Haojian Zhuang <haojian.zhuang@gmail.com>
Acked-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Haojian Zhuang <haojian.zhuang@gmail.com>