Allow updating names in DHCP hosts by matching IPs.
Allow updating names in DHCP hosts by matching IPs.

Also fix the error message if an IPv6 host with no MAC
is not found.

https://bugzilla.redhat.com/show_bug.cgi?id=991290

rlaager/libvirt,agx/libvirt,eskultety/libvirt,nertpinx/libvirt,VenkatDatta/libvirt,jardasgit/libvirt,shugaoye/libvirt,jardasgit/libvirt,nertpinx/libvirt,jardasgit/libvirt,nertpinx/libvirt,taget/libvirt,zippy2/libvirt,datto/libvirt,jardasgit/libvirt,jfehlig/libvirt,eskultety/libvirt,datto/libvirt,VenkatDatta/libvirt,shugaoye/libvirt,olafhering/libvirt,olafhering/libvirt,olafhering/libvirt,jfehlig/libvirt,fabianfreyer/libvirt,fabianfreyer/libvirt,elmarco/libvirt,nertpinx/libvirt,taget/libvirt,fabianfreyer/libvirt,libvirt/libvirt,andreabolognani/libvirt,VenkatDatta/libvirt,crobinso/libvirt,elmarco/libvirt,jardasgit/libvirt,zippy2/libvirt,andreabolognani/libvirt,agx/libvirt,shugaoye/libvirt,fabianfreyer/libvirt,datto/libvirt,rlaager/libvirt,elmarco/libvirt,eskultety/libvirt,agx/libvirt,elmarco/libvirt,rlaager/libvirt,eskultety/libvirt,rlaager/libvirt,taget/libvirt,crobinso/libvirt,olafhering/libvirt,crobinso/libvirt,shugaoye/libvirt,libvirt/libvirt,VenkatDatta/libvirt,andreabolognani/libvirt,andreabolognani/libvirt,zippy2/libvirt,libvirt/libvirt,andreabolognani/libvirt,taget/libvirt,VenkatDatta/libvirt,agx/libvirt,zippy2/libvirt,taget/libvirt,rlaager/libvirt,elmarco/libvirt,jfehlig/libvirt,libvirt/libvirt,datto/libvirt,datto/libvirt,crobinso/libvirt,jfehlig/libvirt,nertpinx/libvirt,agx/libvirt,eskultety/libvirt,shugaoye/libvirt,fabianfreyer/libvirt