pinctrl: intel: Add Intel Emmitsburg pin controller support

This driver adds pinctrl/GPIO support for Intel Emmitsburg PCH. The
GPIO controller is based on the next generation GPIO hardware but still
compatible with the one supported by the Intel core pinctrl/GPIO driver.

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