Write resolve field to zero before using it again

src/lib66/service/service_db_migrate.c

@@ -61,6 +61,8 @@ void service_db_migrate(resolve_service_t *old, resolve_service_t *new, char con
 
                     char *dname = sold.s + pos ;
 
+                    dres = service_resolve_zero ;
+
                     r = resolve_read_g(dwres, base, dname) ;
                     if (r < 0)
                         log_die(LOG_EXIT_USER, "read resolve file of: ") ;