python: Avoid memory leaks on libvirt_virNodeGetCPUStats
python: Avoid memory leaks on libvirt_virNodeGetCPUStats

Detected by valgrind. Leaks are introduced in commit 4955602.

* python/libvirt-override.c (libvirt_virNodeGetCPUStats): fix memory leaks
and improve codes return value.

For details, please see the following link:
RHBZ: https://bugzilla.redhat.com/show_bug.cgi?id=770943

Signed-off-by: Alex Jia <e236faec8cb8371bfb245ba3769a84afc9a11438@redhat.com>

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