linux-phytec-ti

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>