Devices based on Intel SoC products such as Baytrail have a Power
Management IC. In the PMIC there are subsystems for voltage regulation,
A/D conversion, GPIO and PWMs. The PMIC in Baytrail-T platform is
called Crystal Cove.

This patch adds support for the GPIO function in Crystal Cove.
Signed-off-by: NYang, Bin <bin.yang@intel.com>
Signed-off-by: NZhu, Lejun <lejun.zhu@linux.intel.com>
Reviewed-by: NMika Westerberg <mika.westerberg@linux.intel.com>
Reviewed-by: NAlexandre Courbot <acourbot@nvidia.com>
Reviewed-by: NLinus Walleij <linus.walleij@linaro.org>
Signed-off-by: NLee Jones <lee.jones@linaro.org>