[Crash-utility] update for xen hypervisor analysis

Hi, This is an update for xen hypervisor analysis. This patch is diff from crash-4.0-3.13. Note that xen hypervisor analysis in the crash-4.0-3.13 works with a dump taken by before xen-unstable-12502. The format of crash-notes saved in the xen hypervisor changed at xen-unstable-12502 and xen-unstable-12733 (by Magnus). This patch support both before 12502 and after 12502 and after 12733. (ie. all) (support architecture: x86, x86_64) Thanks. -- Itsuro ODA <oda(a)valinux.co.jp&gt;