drivers: charger: add driver for bq25713

Create a driver implementation for the battery charge controller
TI BQ25713.

It includes the ability to enable / disable the controller and also
to setup max current and voltage charge parameters at initialization
time but also at run time.

On the other hand, it is possible to assign / obtain input voltage
and current regulation.

Signed-off-by: Kiara Navarro <knavarro@paltatech.com>