packaging: setup: db secure variables on legacy upgrade

running engine-setup-2 upgrading from legacy
sets ENGINE_DB_SECURED and ENGINE_DB_SECURED_VALIDATION
as it's done in engine-upgrade

Change-Id: Iadcfeb051bf66c220727b1943010b1dbe1112ec5
Signed-off-by: Sandro Bonazzola <sbonazzo@redhat.com>