lttng: cleanup callstack requirement test

lttng: cleanup callstack requirement test

Reduce code duplication using static enum data. The file is 200 lines
shorter and new test are easier to add.

Change-Id: I8a67470d7fab53ca1a46b052bee3aa1354a906fe
Signed-off-by: Francis Giraldeau <francis.giraldeau@gmail.com>
Reviewed-on: https://git.eclipse.org/r/71537
Reviewed-by: Hudson CI
Reviewed-by: Bernd Hufmann <bernd.hufmann@ericsson.com>
Tested-by: Bernd Hufmann <bernd.hufmann@ericsson.com>