staging: unisys: removed unused visor_device.type field

The visor_device.type field was included when preparing to remove
the device_info struct. However, it's not used at all, and was already
redundant by the existence of the 'visor_device.channel_type_guid'
field.

Signed-off-by: Alexander Curtin <alexander.curtin@unisys.com>
Signed-off-by: David Kershner <david.kershner@unisys.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>