Merge remote-tracking branch 'spice/spice.v75' into staging

# By Gerd Hoffmann (2) and others
# Via Gerd Hoffmann
* spice/spice.v75:
  spice: fix multihead support
  spice-display: add display channel id to the debug messages.
  Fix VNC SASL authentication when using a QXL device
  spice: replace use of deprecated API

Message-id: 1382006760[email protected]
Signed-off-by: Anthony Liguori <[email protected]>