phaul/test: exit with a non-zero code in error cases
phaul/test: exit with a non-zero code in error cases

Signed-off-by: Andrei Vagin <74c05afa918858348d6db8037d82fa8124870113@virtuozzo.com>

checkpoint-restore/go-criu,checkpoint-restore/go-criu,checkpoint-restore/go-criu