xenconfig: add domxml conversions for xen-xl

xenconfig: add domxml conversions for xen-xl

This patch converts NUMA configurations between the Xen libxl
configuration file format and libvirt's XML format.

XML HVM domain on a 4 node (2 cores/socket) configuration:

  <cpu>
    <numa>
      <cell id='0' cpus='0-1' memory='2097152' unit='KiB'>
        <distances>
          <sibling id='0' value='10'/>
          <sibling id='1' value='21'/>
          <sibling id='2' value='31'/>
          <sibling id='3' value='21'/>
        </distances>
      </cell>
      <cell id='1' cpus='2-3' memory='2097152' unit='KiB'>
        <distances>
          <sibling id='0' value='21'/>
          <sibling id='1' value='10'/>
          <sibling id='2' value='21'/>
          <sibling id='3' value='31'/>
        </distances>
      </cell>
      <cell id='2' cpus='3-4' memory='2097152' unit='KiB'>
        <distances>
          <sibling id='0' value='31'/>
          <sibling id='1' value='21'/>
          <sibling id='2' value='10'/>
          <sibling id='3' value='21'/>
        </distances>
      </cell>
      <cell id='3' cpus='5-6' memory='2097152' unit='KiB'>
        <distances>
          <sibling id='0' value='21'/>
          <sibling id='1' value='31'/>
          <sibling id='2' value='21'/>
          <sibling id='3' value='10'/>
        </distances>
      </cell>
    </numa>
  </cpu>

Xen xl.cfg domain configuration:

  vnuma = [["pnode=0","size=2048","vcpus=0-1","vdistances=10,21,31,21"],
           ["pnode=1","size=2048","vcpus=2-3","vdistances=21,10,21,31"],
           ["pnode=2","size=2048","vcpus=4-5","vdistances=31,21,10,21"],
           ["pnode=3","size=2048","vcpus=6-7","vdistances=21,31,21,10"]]

If there is no XML <distances> description amongst the <cell> data the
conversion schema from xml to native will generate 10 for local and 20
for all remote instances.

Signed-off-by: Wim ten Have <wim.ten.have@oracle.com>
Reviewed-by: Jim Fehlig <jfehlig@suse.com>
Signed-off-by: Jim Fehlig <jfehlig@suse.com>