* docs/formatdomain.html.in docs/libvirt.rng docs/formatdomain.html:
  document the new PCI passthrough format
* tests/qemuxml2argvtest.c tests/qemuxml2xmltest.c
  tests/qemuxml2argvdata/qemuxml2argv-hostdev-pci-address.args
  tests/qemuxml2argvdata/qemuxml2argv-hostdev-pci-address.xml:
  and add a regression test for it.
Daniel