Merge remote-tracking branch 'remotes/armbru/tags/pull-hw-2015-04-02' into staging

hw: Contain drive, serial, parallel, net misuse

# gpg: Signature made Thu Apr  2 14:32:00 2015 BST using RSA key ID EB918653
# gpg: Good signature from "Markus Armbruster <armbru@redhat.com>"
# gpg:                 aka "Markus Armbruster <armbru@pond.sub.org>"

* remotes/armbru/tags/pull-hw-2015-04-02:
  sysbus: Make devices picking up backends unavailable with -device
  sdhci: Make device "sdhci-pci" unavailable with -device
  hw: Mark device misusing nd_table[] FIXME
  hw: Mark devices picking up char backends actively FIXME
  hw: Mark devices picking up block backends actively FIXME

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>