CONFIG_ARCH_IXP2000 is not available for thedefaultarchitecture x86.
Result is shown for architecture arm
default or selected kernelversion does not have config value CONFIG_ARCH_IXP2000.
Result is shown for kernelversion 6.2.5

IXP2400/2800-based

modulename: uengine.ko

configname: CONFIG_ARCH_IXP2000

ARM system type
└─>IXP2400/2800-based
In linux kernel since version 2.6.12  
Support for Intel's IXP2400/2800 (XScale) family of processors.

source code: