linux-phytec-ti

sh: intc: switch irq_desc iteration to new active IRQ iterator.

There's no need to iterative over every single irq_desc when we can
already work out which IRQs have a backing descriptor via the shiny new
for_each_active_irq(). Switch to that instead.

Signed-off-by: Paul Mundt <lethal@linux-sh.org>