Returns a list of vim.vm.device.VirtualDeviceSpec objects representing
    SCSI controllers

    scsi_devices:
        List of SCSI device properties

def _create_scsi_devices(scsi_devices):
    '''
    Returns a list of vim.vm.device.VirtualDeviceSpec objects representing
    SCSI controllers

    scsi_devices:
        List of SCSI device properties
    '''
    keys = range(-1000, -1050, -1)
    scsi_specs = []
    if scsi_devices:
        devs = [scsi['adapter'] for scsi in scsi_devices]
        log.trace('Creating SCSI devices %s', devs)
        # unitNumber for disk attachment, 0:0 1st 0 is the controller busNumber,
        # 2nd is the unitNumber
        for (key, scsi_controller) in zip(keys, scsi_devices):
            # create the SCSI controller
            scsi_spec = _apply_scsi_controller(scsi_controller['adapter'],
                                               scsi_controller['type'],
                                               scsi_controller['bus_sharing'],
                                               key,
                                               scsi_controller['bus_number'],
                                               'add')
            scsi_specs.append(scsi_spec)
    return scsi_specs