qemu: setvcpus: Save config changes to disk
qemu: setvcpus: Save config changes to disk

Currently changes to the persistent config aren't flushed to disk, meaning
they are lost if the domain is redefined or libvirtd is restarted.

jfehlig/libvirt,iam-TJ/libvirt,wiedi/libvirt,shugaoye/libvirt,soulxu/libvirt-xuhj,novel/fbsd-libvirt,warewolf/libvirt,jardasgit/libvirt,rbu/libvirt,VenkatDatta/libvirt,andreabolognani/libvirt,kantai/libvirt-vfork,danwent/libvirt-ovs,warewolf/libvirt,leilihh/libvirt,rmarwaha/libvirt,rmarwaha/libvirt1,shugaoye/libvirt,crobinso/libvirt,jeckersb/libvirt,foomango/libvirt,agx/libvirt,zhlcindy/libvirt-1.1.4-maintain,leilihh/libvirt,zippy2/libvirt,olafhering/libvirt,crobinso/libvirt,rmarwaha/libvirt1,soulxu/libvirt-xuhj,novel/fbsd-libvirt,kantai/libvirt-vfork,shugaoye/libvirt,trainstack/libvirt,rlaager/libvirt,zhlcindy/libvirt-1.1.4-maintain,olafhering/libvirt,bjzhang/libvirt,libvirt/libvirt,jeckersb/libvirt,trainstack/libvirt,zippy2/libvirt,bjzhang/libvirt,cbosdo/libvirt,iam-TJ/libvirt,bjzhang/libvirt,rbu/libvirt,jeckersb/libvirt,wiedi/libvirt,usc-isi/libvirt,jeckersb/libvirt,trainstack/libvirt,crobinso/libvirt,andreabolognani/libvirt,emaste/libvirt,jfehlig/libvirt,dumbbell/libvirt,VenkatDatta/libvirt,usc-isi/libvirt,wiedi/libvirt,warewolf/libvirt,rmarwaha/libvirt,wiedi/libvirt,andreabolognani/libvirt,nertpinx/libvirt,VenkatDatta/libvirt,zhlcindy/libvirt-1.1.4-maintain,eskultety/libvirt,foomango/libvirt,zippy2/libvirt,nertpinx/libvirt,rmarwaha/libvirt1,jfehlig/libvirt,shugaoye/libvirt,rbu/libvirt,dumbbell/libvirt,jeckersb/libvirt,rmarwaha/libvirt1,jfehlig/libvirt,cbosdo/libvirt,shugaoye/libvirt,siboulet/libvirt-openvz,olafhering/libvirt,rbu/libvirt,dumbbell/libvirt,elmarco/libvirt,rlaager/libvirt,trainstack/libvirt,fabianfreyer/libvirt,leilihh/libvirt,rmarwaha/libvirt1,agx/libvirt,wiedi/libvirt,foomango/libvirt,eskultety/libvirt,VenkatDatta/libvirt,datto/libvirt,zhlcindy/libvirt-1.1.4-maintain,agx/libvirt,cbosdo/libvirt,bjzhang/libvirt,siboulet/libvirt-openvz,novel/fbsd-libvirt,elmarco/libvirt,novel/fbsd-libvirt,emaste/libvirt,wiedi/libvirt,emaste/libvirt,danwent/libvirt-ovs,leilihh/libvirt,jardasgit/libvirt,emaste/libvirt,emaste/libvirt,jeckersb/libvirt,iam-TJ/libvirt,novel/fbsd-libvirt,foomango/libvirt,eskultety/libvirt,usc-isi/libvirt,libvirt/libvirt,dumbbell/libvirt,taget/libvirt,sshah-solarflare/Libvirt-PCI-passthrough-,dumbbell/libvirt,rmarwaha/libvirt,kantai/libvirt-vfork,andreabolognani/libvirt,soulxu/libvirt-xuhj,novel/fbsd-libvirt,fabianfreyer/libvirt,jeckersb/libvirt,warewolf/libvirt,taget/libvirt,libvirt/libvirt,trainstack/libvirt,emaste/libvirt,crobinso/libvirt,libvirt/libvirt,fabianfreyer/libvirt,rmarwaha/libvirt,elmarco/libvirt,nertpinx/libvirt,usc-isi/libvirt,datto/libvirt,sshah-solarflare/Libvirt-PCI-passthrough-,usc-isi/libvirt,elmarco/libvirt,kantai/libvirt-vfork,elmarco/libvirt,kantai/libvirt-vfork,danwent/libvirt-ovs,rbu/libvirt,taget/libvirt,fabianfreyer/libvirt,soulxu/libvirt-xuhj,sshah-solarflare/Libvirt-PCI-passthrough-,leilihh/libvirt,sshah-solarflare/Libvirt-PCI-passthrough-,siboulet/libvirt-openvz,olafhering/libvirt,warewolf/libvirt,dumbbell/libvirt,rmarwaha/libvirt,trainstack/libvirt,eskultety/libvirt,VenkatDatta/libvirt,nertpinx/libvirt,soulxu/libvirt-xuhj,rlaager/libvirt,warewolf/libvirt,zippy2/libvirt,iam-TJ/libvirt,siboulet/libvirt-openvz,eskultety/libvirt,taget/libvirt,datto/libvirt,novel/fbsd-libvirt,jardasgit/libvirt,danwent/libvirt-ovs,fabianfreyer/libvirt,wiedi/libvirt,rlaager/libvirt,cbosdo/libvirt,jardasgit/libvirt,iam-TJ/libvirt,datto/libvirt,emaste/libvirt,sshah-solarflare/Libvirt-PCI-passthrough-,novel/fbsd-libvirt,agx/libvirt,rlaager/libvirt,leilihh/libvirt,jardasgit/libvirt,novel/fbsd-libvirt,cbosdo/libvirt,zhlcindy/libvirt-1.1.4-maintain,agx/libvirt,siboulet/libvirt-openvz,iam-TJ/libvirt,iam-TJ/libvirt,nertpinx/libvirt,bjzhang/libvirt,rmarwaha/libvirt1,rmarwaha/libvirt,trainstack/libvirt,warewolf/libvirt,datto/libvirt,foomango/libvirt,taget/libvirt,danwent/libvirt-ovs,andreabolognani/libvirt