MINOR: tevt: Don't duplicate termination event during reporting

MINOR: tevt: Don't duplicate termination event during reporting

It is hard to never detect the same event several time without painful
tests. In other words, the same termination event can be reported several
time and this must be handled. To do so, "tevt_report_event" macro is
updated to ignore an event if the last reported one is of the same type, for
the same location. Of course, if the same event is reported several times at
different moment, it will not be detected.