iio: adc: cc10001: Use devm_ to call device power down.

iio: adc: cc10001: Use devm_ to call device power down.

It is presumably safe to call the powerdown whether or not we are
in the commented shared state (the driver always did this).

The power down was previously out of order wrt to the probe() function
so move using devm_ will ensure it occurs after the userspace interfaces
are removed.

Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
Reviewed-by: Nuno Sá <nuno.sa@analog.com>
Link: https://lore.kernel.org/r/20221016170950.387751-5-jic23@kernel.org