ss: Remove infinite loop in debugPrint() code

ss: Remove infinite loop in debugPrint() code

In practice extensions are not used, so the value would always
be "-1" and it would never go inside the loop. But if we had
started using extensions it would have infinite looped rather
quickly.

Change-Id: I570437858995d0131a75e735373593caf5d4b25f
Signed-off-by: Alexandre Montplaisir <alexmonthy@efficios.com>
Reviewed-on: https://git.eclipse.org/r/81498
Reviewed-by: Hudson CI
Reviewed-by: Genevieve Bastien <gbastien+lttng@versatic.net>