look for any kind of types, not just POD types, helps to find
smart pointer fields that are only assigned nullptr

Change-Id: I2d887e98db012f03b646e1023985bcc196285abc
Reviewed-on: https://gerrit.libreoffice.org/62382
Tested-by: Jenkins
Reviewed-by: Noel Grandin <noel.grandin@collabora.co.uk>