Revert "gpio: thunderx: Switch to GPIOLIB_IRQCHIP"

Revert "gpio: thunderx: Switch to GPIOLIB_IRQCHIP"

This reverts commit a7fc89f9d5fcc10a5474cfe555f5a9e5df8b0f1f because
there are some bugs in this commit, and we don't have a simple way to
fix these bugs. So revert this commit to make the thunderx gpio work
on the stable kernel at least. We will switch to GPIOLIB_IRQCHIP
for thunderx gpio by following patches.

Fixes: a7fc89f9d5fc ("gpio: thunderx: Switch to GPIOLIB_IRQCHIP")
Signed-off-by: Kevin Hao <haokexin@gmail.com>
Link: https://lore.kernel.org/r/20200114082821.14015-2-haokexin@gmail.com
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>