staging: unisys: include: reorder to avoid forward declaration

The include file visorbus.h has a forward declaration of visor_device.
A simple reorder of the file removed the need for the forward
declaration.

Signed-off-by: David Kershner <david.kershner@unisys.com>
Reviewed-by: Tim Sell <timothy.sell@unisys.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>