staging:iio:dummy: Remove outdated comment
iio_device_free has to be called regardless of whether the device has been
registered or not when freeing it.
Signed-off-by: Lars-Peter Clausen <lars@metafoo.de>
Acked-by: Jonathan Cameron <jic23@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>