genirq: Look-up percpu trigger type if not specified by caller

As we now do for non-percpu interrupt, perform a lookup of the
interrupt trigger if the user doesn't supply one. The difference
here is that we can only do it at enable time (trigger configuration
can be per-cpu as well).
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>

kernel/irq/manage.c

@@ -1737,7 +1737,14 @@ void enable_percpu_irq(unsigned int irq, unsigned int type)
 	if (!desc)
 		return;
 
+	/*
+	 * If the trigger type is not specified by the caller, then
+	 * use the default for this interrupt.
+	 */
 	type &= IRQ_TYPE_SENSE_MASK;
+	if (type == IRQ_TYPE_NONE)
+		type = irqd_get_trigger_type(&desc->irq_data);
+
 	if (type != IRQ_TYPE_NONE) {
 		int ret;