nine: call DBG() at more external entry points

Signed-off-by: Stanislaw Halik <sthalik@misaki.pl>
Reviewed-by: David Heidelberg <david@ixit.cz>
Reviewed-by: Axel Davy <axel.davy@ens.fr>
Merge pull request #30 from sthalik/dbg-calls

call DBG() for external entry points