Implement the irq_set_type() callback and call irqd_set_trigger_type()
internally so that users interested in the configured trigger type can
later retrieve it using irqd_get_trigger_type(). We only support edge
trigger types.

Signed-off-by: Bartosz Golaszewski <bgolaszewski@baylibre.com>
Acked-by: Marc Zyngier <marc.zyngier@arm.com>