CONFIG_POWERPMC250 is not available for thedefaultarchitecture x86.
Result is shown for architecture ppc

Force-PowerPMC250

modulename: pci_auto.ko

and/or

powerpmc250.ko

configname: CONFIG_POWERPMC250

Machine Type
└─>Force-PowerPMC250
In linux kernel since version 2.6.20 (release Date: 2007-02-04)  
source code:
arch/ppc/syslib/pci_auto.c
is selected by
CONFIG_MPC10X_BRIDGE