tmf: Speed up TmfTraceUtils#getPreviousEventMatching

tmf: Speed up TmfTraceUtils#getPreviousEventMatching

This patch makes the reverse search look back by the cache
size of the trace, then iterating on the chunk in reverse
order to find a match. This allows returning as soon as
we find a matching event.

Change-Id: Iaed2c2326d5a4939688df7ba6d13696811d1c165
Signed-off-by: Matthew Khouzam <matthew.khouzam@ericsson.com>
Signed-off-by: Alexandre Montplaisir <alexmonthy@efficios.com>
Reviewed-on: https://git.eclipse.org/r/76164
Reviewed-by: Hudson CI
Reviewed-by: Patrick Tasse <patrick.tasse@gmail.com>