tmf: Fix duplicate trace check in TmfOpenTraceHelper

tmf: Fix duplicate trace check in TmfOpenTraceHelper

If the provided path was a convoluted path which resolved to the same
path as an existing trace location of the same name, it was incorrectly
considered a different trace and renamed with a numbered suffix.

Change-Id: Ic802cd5ffd83c5a29e422dfddbb0463aca1b372a
Signed-off-by: Patrick Tasse <patrick.tasse@gmail.com>
Reviewed-on: https://git.eclipse.org/r/62136
Reviewed-by: Bernd Hufmann <bernd.hufmann@ericsson.com>
Tested-by: Bernd Hufmann <bernd.hufmann@ericsson.com>
Reviewed-by: Hudson CI