altos: Lost change that reported flight 0 when log memory was full

commit 52ac83fedbfd380d14d4df2e79992bbdfba3552a added coded to check
for a full flight log and complain with a special tone.

It also reported flight 0 over telemetry, and that part of the patch
got lost when moving to the new telemetry format. This patch
resurrects that piece.

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