Staging: iio: trigger: Add module name information in Kconfig

This patch updates Kconfig with paragraphs that describe config symbol fully.
Found using checkpatch.pl.

Signed-off-by: Darshana Padmadas <darshanapadmadas@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>