staging:iio:ad2s1210: Remove end of line with '['

This patch fixes the checkpatch.pl check:

iio/resolver/ad2s1210.c:202: CHECK: Lines should not end with a '['

Signed-off-by: Rodrigo Siqueira <rodrigosiqueiramelo@gmail.com>
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>