Fix a use-after-free (or double-free) due to net_cleanup() freeing NICs
that don't belong to it, fix a newly-introduced launch failure with a
documented command line, and clean up code to avoid a Coverity warning.

David Woodhouse (3):
      net: do not delete nics in net_cleanup()
      vl: disable default serial when xen-console is enabled
      hw/xen: clean up xen_block_find_free_vdev() to avoid Coverity false positive

 hw/block/xen-block.c | 24 +++++++++++++++++++++---
 net/net.c            | 28 ++++++++++++++++++++++------
 system/vl.c          |  1 +
 3 files changed, 44 insertions(+), 9 deletions(-)