tracing/events: add trace-events-sample

This patch adds a sample to the samples directory on how to create
and use TRACE_EVENT trace points.

Signed-off-by: Steven Rostedt <rostedt@goodmis.org>

diff --cc samples/Kconfig
Simple merge

diff --cc samples/Makefile
Simple merge

diff --cc samples/trace_events/Makefile
Simple merge

diff --cc samples/trace_events/trace-events-sample.c
Simple merge

diff --cc samples/trace_events/trace-events-sample.h
Simple merge