irqchip/bcm2835: Enable SKIP_SET_WAKE and MASK_ON_SUSPEND

The BCM2835 ARMCTRL interrupt controller doesn't provide any facility to
configure the wakeup sources. That's the reason why the driver lacks the
irq_set_wake() callback for the interrupt chip.

But this prevent to properly enter power management states like "suspend to
idle".

Enable the flags IRQCHIP_SKIP_SET_WAKE and IRQCHIP_MASK_ON_SUSPEND so the
interrupt suspend logic can handle the chip correctly.

Signed-off-by: Stefan Wahren <wahrenst@gmx.net>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Florian Fainelli <florian.fainelli@broadcom.com>