power: supply: qcom: Initial version driver for SMB1398 charger

This is the initial driver for SMB1398 charger. It can work at CP mode
to provide DIV2 charging mode solution, it can also work as a pre-regultor
which helps to regulate the power from wireless receiver and provides
constant voltage/current input for down streaming chargers.

Change-Id: Id09e25b1d5290d22102188ab905a94956be0c410
Signed-off-by: Fenglin Wu <fenglinw@codeaurora.org>
Signed-off-by: Ashish Chavan <ashichav@codeaurora.org>