kernelconfig_penguin
CONFIG_MACH_IXP4XX_OF is not available for the default architecture x86.
Result is shown for architecture arm

Devce Tree IXP4xx boards

configname: CONFIG_MACH_IXP4XX_OF

Linux Kernel Configuration
└─> Intel IXP4xx Implementation Options
└─> Devce Tree IXP4xx boards

Say 'Y' here to support Device Tree-based IXP4xx platforms.