staging: unisys: visorbus: remove noisy postcodes

Get rid of postcodes from visorbus_main.c that are just informational.

They were not logging errors, we don't need to replace them with
anything.

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>