tools lib traceevent, perf tools: Rename traceevent_plugin_* APIs

tools lib traceevent,  perf tools: Rename traceevent_plugin_* APIs

In order to make libtraceevent into a proper library, variables, data
structures and functions require a unique prefix to prevent name space
conflicts. That prefix will be "tep_" and not "traceevent_". This changes
APIs: traceevent_plugin_list_options, traceevent_plugin_free_options_list,
traceevent_plugin_add_options, traceevent_plugin_remove_options,
traceevent_print_plugins

Signed-off-by: Tzvetomir Stoyanov (VMware) <tz.stoyanov@gmail.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Yordan Karadzhov (VMware) <y.karadz@gmail.com>
Cc: linux-trace-devel@vger.kernel.org
Link: http://lkml.kernel.org/r/20180808180702.089951638@goodmis.org
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>