kernelconfig_penguin
CONFIG_ARCH_PXA is not available for the default architecture x86.
Result is shown for architecture arm

PXA2xx/PXA3xx-based

configname: CONFIG_ARCH_PXA

ARM system type
└─> PXA2xx/PXA3xx-based

In linux kernel since version 2.6.12  

Support for Intel/Marvell's PXA2xx/PXA3xx processor line.