pinctrl: intel: Add support for hardware debouncer

The next generation Intel GPIO hardware has two additional registers
PADCFG2 and PADCFG3. The latter is marked as reserved but the former
includes configuration for per-pad hardware debouncer.

This patch adds support for that in the Intel pinctrl core driver. Since
these are additional features on top of the current generation hardware,
we use revision number and feature flags to enable this if detected.

Signed-off-by: Mika Westerberg <mika.westerberg@linux.intel.com>
Reviewed-by: Andy Shevchenko <andy.shevchenko@gmail.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>