Input: da9063_onkey - avoid explicitly setting input's parent

devm_input_allocate_device() already sets parent of the new input
device, there's no need to set it up explicitly.

Reviewed-by: Biju Das <biju.das.jz@bp.renesas.com>
Link: https://lore.kernel.org/r/ZYOseYfVgg0Ve6Zl@google.com


Signed-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>