schema: Fix capability grammar for pagesElem

schema: Fix capability grammar for pagesElem

https://bugzilla.redhat.com/show_bug.cgi?id=1572491

Commit id '02129b7c0' added a single pagesElem for slightly
different purposes. One usage was an output for host page size
listing and the other for NUMA supported page sizes. For the
former, only the pages unit and size are formatted, while for
the latter the pages unit, size, and availability data is formatted.

The virt-xml-validate would fail because it expected something
extra in the host page size output. So split up pagesElem a bit
and create pagesHost and pagesNuma for the differences.

Modify some capabilityschemadata output to have the output - even
though the results may not be realistic with respect to the
original incarnation of the data.

Signed-off-by: John Ferlan <jferlan@redhat.com>
ACKed-by Michal Privoznik <mprivozn@redhat.com>