trace-cmd: Add Developer's Certificate of Origin document "DCO"

To formalize exactly what a Signed-off-by means in a commit log, add the DCO
document that explains it.

Suggested-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
1 file changed