If a second dummy client that talks to the actual I2C address was
created in probe(), there should be a proper cleanup on driver and
device removal to avoid leakage.

So unregister the dummy client via another callback.
Reviewed-by: Hans de Goede <hdegoede@redhat.com>
Suggested-by: Hans de Goede <hdegoede@redhat.com>
Fixes: c1e62062 ("iio: light: cm32181: Handle CM3218 ACPI devices with 2 I2C resources")
Bugzilla: https://bugzilla.redhat.com/show_bug.cgi?id=2152281Signed-off-by: Kai-Heng Feng <kai.heng.feng@canonical.com>
Link: https://lore.kernel.org/r/20230223020059.2013993-1-kai.heng.feng@canonical.com
Cc: <Stable@vger.kernel.org>
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>