irqchip/crossbar: Restore the mask on suspend behaviour

The ARM GIC requires that all interrupts which are not used as a
wakeup source have to be masked during suspend.

The conversion of the crossbar irqchip to hierarchical irq domains
failed to mark the crossbar irqchip with the IRQCHIP_MASK_ON_SUSPEND
flag and therefor broke the suspend requirement of the GIC.

Before the conversion the flags were visible because the GIC was the
top level irqchip. After the conversion the crossbar irqchip is the
top level irq chip whose flags are evaluated in suspend_device_irq().
As the flag is not set the masking of the non-wakeup irqs is not
invoked which breaks suspend.

Add the IRQCHIP_MASK_ON_SUSPEND flag to the crossbar irqchip, so the
GIC interrupts get masked properly.

[ tglx: Massaged changelog ]

Fixes: 783d31863fb8 ('irqchip: crossbar: Convert dra7 crossbar...')
Signed-off-by: Grygorii Strashko <grygorii.strashko@ti.com>
Cc: Sudeep Holla <sudeep.holla@arm.com>
Cc: <linux@arm.linux.org.uk>
Cc: <nsekhar@ti.com>
Cc: <jason@lakedaemon.net>
Cc: <balbi@ti.com>
Cc: <linux-arm-kernel@lists.infradead.org>
Cc: <tony@atomide.com>
Cc: <marc.zyngier@arm.com>
Cc: stable@vger.kernel.org # 4.1
Link: http://lkml.kernel.org/r/1439554830-19502-6-git-send-email-grygorii.strashko@ti.com
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>

drivers/irqchip/irq-crossbar.c

@@ -70,6 +70,7 @@ static struct irq_chip crossbar_chip = {
 	.irq_retrigger		= irq_chip_retrigger_hierarchy,
 	.irq_set_wake		= irq_chip_set_wake_parent,
 	.irq_set_type		= irq_chip_set_type_parent,
+	.flags			= IRQCHIP_MASK_ON_SUSPEND,
 #ifdef CONFIG_SMP
 	.irq_set_affinity	= irq_chip_set_affinity_parent,
 #endif