Look up the battery using the "monitored-battery" phandle
as is nowadays a standard DT binding. The actual bindings
for these charger elements are not upstream so let's sort
out this mess by conforming to the standard.
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Sebastian Reichel <sebastian.reichel@collabora.com>