Improve on virAtomic implementation
Improve on virAtomic implementation

This patch improves the previously added virAtomicInt implementation
by using gcc-builtins if possible. The needed builtins are available
since GCC >= 4.1. At least the 4.0 docs don't mention them.


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