staging: unisys: visorbus: remove POSTCODE in create_bus_instance

Remove postcodes from create_bus_instance. If there is an error log
it with dev_err.

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>