driver core: use IS_ERR_OR_NULL() helper in device_create_groups_vargs()

Use IS_ERR_OR_NULL() helper in device_create_groups_vargs() to simplify code
and improve readiblity. No functional change.

Signed-off-by: Yang Yingliang <yangyingliang@huawei.com>
Link: https://lore.kernel.org/r/20220914140753.3799982-1-yangyingliang@huawei.com


Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>