[xen/f20] (2 commits) ...use-after-free in xc_cpupool_getinfo() under memory pressure

[myoung]

Summary of changes:

  eafedbe... add bug and CVE references to most recent changelog entry (*)
  cf73ea5... use-after-free in xc_cpupool_getinfo() under memory pressur (*)

(*) This commit already existed in another branch; no separate mail sent