pnpbios: bail out on strange errors

A small number of systems respond to PnP dock queries with bogus values.
This causes us to keep logging an error every 2 seconds. Instead of trying
again just assume the BIOS is crapware and doesn't actually have dock
functionality.

Signed-off-by: Alan Cox <alan@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>