qapi-schema: add 'device_add'

##

{ 'command': 'xen-set-global-dirty-log', 'data': { 'enable': 'bool' } }

##

# @device_add:

#

# @driver: the name of the new device's driver

#

# @bus: #optional the device's parent bus (device tree path)

#

# @id: the device's ID, must be unique

#

# Additional arguments depend on the type.

#

# Add a device.

#

# Notes:

# 1. For detailed information about this command, please refer to the

#    'docs/qdev-device-use.txt' file.

#

# 2. It's possible to list device properties by running QEMU with the

#    "-device DEVICE,help" command-line argument, where DEVICE is the

#    device's name

#

# Example:

#

# -> { "execute": "device_add",

#      "arguments": { "driver": "e1000", "id": "net1",

#                     "bus": "pci.0",

#                     "mac": "52:54:00:12:34:56" } }

# <- { "return": {} }

#

# TODO This command effectively bypasses QAPI completely due to its

# "additional arguments" business.  It shouldn't have been added to

# the schema in this form.  It should be qapified properly, or

# replaced by a properly qapified command.

#

# Since: 0.13

##

{ 'command': 'device_add',

  'data': {'driver': 'str', 'id': 'str'},

  'gen': false } # so we can get the additional arguments

##

# @device_del:

#