attached io in HasIO must not be mandatory - either uri or io
has to be given
Change-Id: Id39e40f98020d4051c1ad8105f6af6018aafaea8
Reviewed-on: https://forge.frm2.tum.de/review/c/sine2020/secop/playground/+/29349
Tested-by: Jenkins Automated Tests <pedersen+jenkins@frm2.tum.de>
Reviewed-by: Enrico Faulhaber <enrico.faulhaber@frm2.tum.de>
Reviewed-by: Markus Zolliker <markus.zolliker@psi.ch>