CONFIG_PXA25x is not available for the selected architecture x86.
Result is shown for architecture arm

CONFIG_PXA25x (not configurable)

modulename: pxa25x.ko

configname: CONFIG_PXA25x

Linux Kernel Configuration
└─>PXA25x
In linux kernel since version 2.6.20 (release Date: 2007-02-04)
Select code specific to PXA21x/25x/26x variants
source code: