power/supply: ingenic-battery: Don't print error on -EPROBE_DEFER

Don't print an error message if devm_power_supply_register() returns
-EPROBE_DEFER, since the driver will simply re-probe later.

Signed-off-by: Paul Cercueil <paul@crapouillou.net>
Signed-off-by: Sebastian Reichel <sebastian.reichel@collabora.com>