virsh: only report filled values in nodecpustats
virsh: only report filled values in nodecpustats

Rewrite the function to use an array instead of a struct,
translating the field names to int via an enum.

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