apparmor: allow libvirt to send term signal to unconfined
apparmor: allow libvirt to send term signal to unconfined

Otherwise stopping domains with qemu://session fails like

[164012.338157] audit: type=1400 audit(1516202208.784:99): apparmor="DENIED" operation="signal" profile="/usr/sbin/libvirtd" pid=18835 comm="libvirtd" requested_mask="send" denied_mask="send" signal=term peer="unconfined"

jardasgit/libvirt,crobinso/libvirt,libvirt/libvirt,fabianfreyer/libvirt,olafhering/libvirt,eskultety/libvirt,eskultety/libvirt,zippy2/libvirt,andreabolognani/libvirt,olafhering/libvirt,fabianfreyer/libvirt,nertpinx/libvirt,crobinso/libvirt,zippy2/libvirt,andreabolognani/libvirt,eskultety/libvirt,eskultety/libvirt,crobinso/libvirt,jardasgit/libvirt,libvirt/libvirt,zippy2/libvirt,andreabolognani/libvirt,jardasgit/libvirt,libvirt/libvirt,nertpinx/libvirt,olafhering/libvirt,zippy2/libvirt,fabianfreyer/libvirt,andreabolognani/libvirt,libvirt/libvirt,jfehlig/libvirt,nertpinx/libvirt,fabianfreyer/libvirt,eskultety/libvirt,jardasgit/libvirt,crobinso/libvirt,jfehlig/libvirt,jfehlig/libvirt,andreabolognani/libvirt,olafhering/libvirt,jardasgit/libvirt,nertpinx/libvirt,jfehlig/libvirt,fabianfreyer/libvirt,nertpinx/libvirt