samples/sensor: Add sample to read RTIO stream using drdy

Add sample to read from up to 10 streaming devices, using the
sensor_stream() API and the RTIO framework:
    https://docs.zephyrproject.org/latest/services/rtio/index.html



The devices has to be aliased as streamN (0 <= N <= 9) in DT, and
will be instantiated using SENSOR_DT_STREAM_IODEV() macro.

Currently the sample gets/prints data on SENSOR_TRIG_DATA_READY
trigger basis for the following sensor channels:

        - SENSOR_CHAN_ACCEL_XYZ

Signed-off-by: Armando Visconti <armando.visconti@st.com>