Updated libvirt package fixes security vulnerabilities

It was discovered that libvirt incorrectly handled certain memory stats requests. A remote attacker could use this issue to cause libvirt to crash, resulting in a denial of service (CVE-2013-4296). It was discovered that libvirt incorrectly handled certain bitmap operations. A remote attacker could use this issue to cause libvirt to crash, resulting in a denial of service (CVE-2013-5651). Additionally, an update for a PolicyKit security issue required libvirt to be updated to use a different API that is not affected by this security issue (CVE-2013-4311).