staging:iio:__lis3l02dq_write_data_ready_config: Pass IIO device directly

When calling __lis3l02dq_write_data_ready_config we pass the device struct of
embedded in the IIO device only to look up the IIO device from the device struct
again right away. This patch changes the code to pass the IIO device directly.

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>