Fix hotplugging of block device-backed usb disks
Fix hotplugging of block device-backed usb disks

Commit ca91ba7 moved qemuSetupDiskCgroup into the qemuDomainPrepareDisk
helper, but failed to call it for usb disks.

https://bugzilla.redhat.com/show_bug.cgi?id=1175668`

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