[PATCH v1] Add in kexec -S for status, and add new Xen hypercall to support this.

[Konrad Rzeszutek Wilk]

Heya!

I am cross-posting on two mailing lists:
 xen-devel at lists.xenproject.org
 kexec at lists.infradead.org

as it may be easier to review and provide input then me going back and forth.

Anyhow the patches are to help with the various distro's poking in
/sys/../kexec to figure out whether an kexec image is loaded.

This can be done using the -S parameter now with the patch #2.

Also I add an hypercall to Xen so that if kexec is running under Xen
the same information can be retrieved (see patch #1).

Thanks!