staging: unisys: visorbus: rectify kerneldoc comment for struct

Fixes the kerneldoc comment for struct visor_device - the struct members
were not listed with the appropriate @ prefix.

Signed-off-by: David Binder <david.binder@unisys.com>
Acked-By: Neil Horman <nhorman@tuxdriver.com>
Reviewed-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>