93330cf542
This allows backend implementations left optional interface methods. For mandatory methods assertion checks added. Took the opportunity to remove unused methods: - tpm_backend_get_desc() - TPMDriverOps->handle_startup_error Signed-off-by: Amarnath Valluri <amarnath.valluri@intel.com> Reviewed-by: Marc-André Lureau <marcandre.lureau@redhat.com> Reviewed-by: Stefan Berger<stefanb@linux.vnet.ibm.com> Signed-off-by: Stefan Berger <stefanb@linux.vnet.ibm.com>