Staging: iio: ad7746: Adjust arguments to match open parenthesis

This patch clears all checkpatch.pl CHECKS, about alignment not matching
open parenthesis, whenever it is possible without going beyond 80 columns.
Signed-off-by: David Veenstra <davidjulianveenstra@gmail.com>
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>