The Spreadtrum SC9860 platform has one SC2731 PMIC, and the SC2731
PMIC integrates all mobile handset power management, audio codec,
battery management and user interface support function in a single
chip.

This patch adds the SC2731 dts file, as well as adding the RTC and
regulator device node for this PMIC.
Signed-off-by: Baolin Wang <baolin.wang@linaro.org>
Signed-off-by: Arnd Bergmann <arnd@arndb.de>