mfd: Add rtc support to 88pm860x

Enable rtc function in 88pm860x PMIC.

Signed-off-by: Haojian Zhuang <haojian.zhuang@marvell.com>
Cc: Alessandro Zummo <a.zummo@towertech.it>
Signed-off-by: Samuel Ortiz <sameo@linux.intel.com>
5 files changed