qemu: fix use-after-free regression
qemu: fix use-after-free regression

Commit baade4d fixed a memory leak on failure, but in the process,
introduced a use-after-free on success, which can be triggered with:

1. set bandwidth with --live
2. query bandwidth
3. set bandwidth with --live

* src/qemu/qemu_driver.c (qemuDomainSetInterfaceParameters): Don't
free newBandwidth on success.
Reported by Hu Tao.

taget/libvirt,novel/fbsd-libvirt,trainstack/libvirt,iam-TJ/libvirt,novel/fbsd-libvirt,emaste/libvirt,zhlcindy/libvirt-1.1.4-maintain,rmarwaha/libvirt1,novel/fbsd-libvirt,warewolf/libvirt,olafhering/libvirt,eskultety/libvirt,foomango/libvirt,datto/libvirt,novel/fbsd-libvirt,siboulet/libvirt-openvz,agx/libvirt,libvirt/libvirt,zippy2/libvirt,jeckersb/libvirt,VenkatDatta/libvirt,foomango/libvirt,novel/fbsd-libvirt,jeckersb/libvirt,foomango/libvirt,rmarwaha/libvirt,zhlcindy/libvirt-1.1.4-maintain,rmarwaha/libvirt,iam-TJ/libvirt,nertpinx/libvirt,datto/libvirt,shugaoye/libvirt,fabianfreyer/libvirt,cbosdo/libvirt,elmarco/libvirt,fabianfreyer/libvirt,cbosdo/libvirt,trainstack/libvirt,fabianfreyer/libvirt,danwent/libvirt-ovs,jardasgit/libvirt,bjzhang/libvirt,dumbbell/libvirt,dumbbell/libvirt,taget/libvirt,bjzhang/libvirt,crobinso/libvirt,libvirt/libvirt,jfehlig/libvirt,jfehlig/libvirt,andreabolognani/libvirt,VenkatDatta/libvirt,iam-TJ/libvirt,wiedi/libvirt,cbosdo/libvirt,nertpinx/libvirt,novel/fbsd-libvirt,cbosdo/libvirt,agx/libvirt,crobinso/libvirt,siboulet/libvirt-openvz,libvirt/libvirt,emaste/libvirt,eskultety/libvirt,siboulet/libvirt-openvz,dumbbell/libvirt,bjzhang/libvirt,shugaoye/libvirt,fabianfreyer/libvirt,jeckersb/libvirt,jardasgit/libvirt,rlaager/libvirt,andreabolognani/libvirt,emaste/libvirt,nertpinx/libvirt,trainstack/libvirt,VenkatDatta/libvirt,olafhering/libvirt,elmarco/libvirt,dumbbell/libvirt,novel/fbsd-libvirt,iam-TJ/libvirt,eskultety/libvirt,siboulet/libvirt-openvz,agx/libvirt,zhlcindy/libvirt-1.1.4-maintain,wiedi/libvirt,warewolf/libvirt,rlaager/libvirt,rmarwaha/libvirt1,foomango/libvirt,rmarwaha/libvirt1,jfehlig/libvirt,rmarwaha/libvirt,wiedi/libvirt,rlaager/libvirt,iam-TJ/libvirt,rmarwaha/libvirt,wiedi/libvirt,rlaager/libvirt,crobinso/libvirt,eskultety/libvirt,zippy2/libvirt,bjzhang/libvirt,agx/libvirt,agx/libvirt,fabianfreyer/libvirt,novel/fbsd-libvirt,iam-TJ/libvirt,emaste/libvirt,olafhering/libvirt,emaste/libvirt,zippy2/libvirt,danwent/libvirt-ovs,VenkatDatta/libvirt,bjzhang/libvirt,elmarco/libvirt,jeckersb/libvirt,andreabolognani/libvirt,siboulet/libvirt-openvz,andreabolognani/libvirt,danwent/libvirt-ovs,novel/fbsd-libvirt,elmarco/libvirt,datto/libvirt,datto/libvirt,nertpinx/libvirt,warewolf/libvirt,warewolf/libvirt,datto/libvirt,iam-TJ/libvirt,jeckersb/libvirt,trainstack/libvirt,zippy2/libvirt,shugaoye/libvirt,dumbbell/libvirt,eskultety/libvirt,jeckersb/libvirt,rmarwaha/libvirt1,cbosdo/libvirt,jfehlig/libvirt,wiedi/libvirt,andreabolognani/libvirt,libvirt/libvirt,rmarwaha/libvirt,nertpinx/libvirt,wiedi/libvirt,zhlcindy/libvirt-1.1.4-maintain,VenkatDatta/libvirt,foomango/libvirt,danwent/libvirt-ovs,rlaager/libvirt,emaste/libvirt,jardasgit/libvirt,zhlcindy/libvirt-1.1.4-maintain,jardasgit/libvirt,dumbbell/libvirt,taget/libvirt,warewolf/libvirt,taget/libvirt,crobinso/libvirt,shugaoye/libvirt,rmarwaha/libvirt1,trainstack/libvirt,rmarwaha/libvirt1,warewolf/libvirt,rmarwaha/libvirt,wiedi/libvirt,trainstack/libvirt,jardasgit/libvirt,taget/libvirt,shugaoye/libvirt,elmarco/libvirt,olafhering/libvirt,emaste/libvirt,trainstack/libvirt,jeckersb/libvirt,warewolf/libvirt,danwent/libvirt-ovs