iio: Move iio userspace applications out of staging

This patch moves iio userspace applications out of staging, to tools/iio/
and adds a Makefile in order to compile them easily. It also adds tools/iio/
to MAINTAINERS file.

Signed-off-by: Roberta Dobrescu <roberta.dobrescu@gmail.com>
Signed-off-by: Jonathan Cameron <jic23@kernel.org>

diff --cc MAINTAINERS
Simple merge

diff --cc tools/iio/Makefile
Simple merge

diff --cc tools/iio/generic_buffer.c
Simple merge

diff --cc tools/iio/iio_event_monitor.c
Simple merge

diff --cc tools/iio/iio_utils.c
Simple merge

diff --cc tools/iio/iio_utils.h
Simple merge

diff --cc tools/iio/lsiio.c
Simple merge