Otherwise test with -d option get fail (this is because
SIGTRAP get cleared by our parasizte engine).

The proper fix most likely will require kernel patching
or redesign of parasite code. Meanwhile to make test
working we switch to the signal which just known to work.
Reported-by: Andrey Vagin <avagin@openvz.org>
Signed-off-by: Cyrill Gorcunov <gorcunov@openvz.org>
Acked-by: Andrew Vagin <avagin@parallels.com>
Signed-off-by: Pavel Emelyanov <xemul@parallels.com>