rtc: Add rtc support to 88PM80X PMIC

add rtc driver for MARVELL 88PM80X PMIC and enable rtc function.

Cc: Alessandro Zummo <a.zummo@towertech.it>
Signed-off-by: Qiao Zhou <zhouqiao@marvell.com>
Signed-off-by: Samuel Ortiz <sameo@linux.intel.com>
3 files changed