altos: Split out tiny telemetry from full telemetry

The TeleMini and TeleNano boards do not have either GPS or
accelermeters, and they also run the kalman filter which produces
standard unit measurements for the flight height/speed/accel
values. This makes the telemetry significantly
different. ao_telemetry_tiny.c sends the required data.

Note that TeleNano sends the same telemetry as telemini at this point;
there are a couple of values which are not useful, but the overhead of
sending them is small enough that the hassle of having three telemetry
formats seemed excessive.

Signed-off-by: Keith Packard <keithp@keithp.com>