The default value is 16 IRQs. Zylonite needs 32, ASIC3 based boards need 70.

My problem is still that due to the way IRQ_GPIO is hardcoded, ASIC3 based boards
need 70 IRQs starting at IRQ_BOARD_START. If I define ASIC3 IRQs similar to LoCoMo
or SA1111, things break as soon as something selects PXA_HAVE_BOARD_IRQS.
Increasing the default number of board IRQs to 70 instead doesn't seem very nice.
Signed-off-by: Philipp Zabel <philipp.zabel@gmail.com>
Signed-off-by: Eric Miao <eric.miao@marvell.com>