The platform data was missing the num_registers element which is now
mandatory in linux 4.9
Without this patch, the gpio probing would fail with:
gpio gpiochip1: (74x164): tried to insert a GPIO chip with zero lines
Fixes: #1106
Tested-by: Robert Marko <robimarko@gmail.com>
Signed-off-by: Thibaut VARENE <hacks@slashdirt.org>