conf: Fix the problem which cause libvirtd to crash
conf: Fix the problem which cause libvirtd to crash

* src/conf/domain_conf.c: Use STREQ_NULLABLE instead of STREQ,
as def->seclables[i]->model could be NULL.

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