one cron job attempts to print debug text into stderr; so the file
of /root/dead.letter gets created and its size grows continuously.
It could eventually threaten dom0 disk space. Maybe there are two
solutions: one is to redirect the output to a specific log file;
and rotate log files in the script. And the other one is simply
to redirect the output /dev/null. By considering the function of
this cron job and the printed contents are straight and simple,
this patch set goes with the later solution.
Change-Id: I4875e5e3837e6f0249e314c6c5f408c79145c6c1
Closes-Bug: 1503966