SVTOOLS : Remove usage of DBG_CTOR and DBG_DTOR.

Valgrind is capable of detecting such bugs. No need for extra macros.

Change-Id: I83e39d69deaf2aa1c5ca455c92d070a2d33def3f
Reviewed-on: https://gerrit.libreoffice.org/8421
Reviewed-by: Caolán McNamara <caolanm@redhat.com>
Tested-by: Caolán McNamara <caolanm@redhat.com>