mfd: intel_soc_pmic: Crystal Cove support

This patch provides chip-specific support for Crystal Cove. Crystal
Cove is the PMIC in Baytrail-T platform.

Also adds Intel SoC PMIC support to the build files.

Signed-off-by: Yang, Bin <bin.yang@intel.com>
Signed-off-by: Zhu, Lejun <lejun.zhu@linux.intel.com>
Signed-off-by: Lee Jones <lee.jones@linaro.org>