power: supply: smb347-charger: Drop pdata support

There are no platforms using the pdata support, so let's
drop it to simplify the driver.

Reviewed-by: Dmitry Osipenko <digetx@gmail.com>
Tested-by: Dmitry Osipenko <digetx@gmail.com>
Signed-off-by: Sebastian Reichel <sebastian.reichel@collabora.com>