event: avoid memory leak on cleanup
event: avoid memory leak on cleanup

Detected by Coverity.  Introduced in commit aaf2b70, and turned into
a regression in the next few commits through 4e6e6672 (unreleased).

* src/conf/domain_event.c (virDomainEventStateFree): Free object,
per documentation.

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