Add missing checks for NULL in domain lock manager
Add missing checks for NULL in domain lock manager

The domain lock manager forgot to include a bunch of checks
for NULL which could occur on OOM

* src/locking/domain_lock.c: Add checks for NULL

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