sbs-battery: export manufacturer and model name to sysfs

This CL supports two power_supply_property items for smart battery:
POWER_SUPPLY_PROP_MANUFACTURER and POWER_SUPPLY_PROP_MODEL_NAME such
that battery information 'manufacturer' and 'model_name' can be exported
to sysfs.

Signed-off-by: Cheng-Yi Chiang <cychiang@chromium.org>
Reviewed-by: Olof Johansson <olofj@chromium.org>
Signed-off-by: Javier Martinez Canillas <javier.martinez@collabora.co.uk>
Signed-off-by: Sebastian Reichel <sre@kernel.org>