In commit 47cb035560a41bd1bd3db506eeab93088815203e, the ax88796 driver
learned to take IRQ flags from platform_device definition. Use that here
to get rid of the set_irq_type() hack.
Signed-off-by: Daniel Mack <daniel@caiaq.de> Signed-off-by: Eric Miao <eric.miao@marvell.com>