CONFIG_MACH_APE6EVM_REFERENCE is not available for thedefaultarchitecture x86.
Result is shown for architecture arm

APE6EVM board - Reference Device Tree Implementation

modulename: board-ape6evm-reference.ko

configname: CONFIG_MACH_APE6EVM_REFERENCE

Linux Kernel Configuration
└─>APE6EVM board - Reference Device Tree Implementation
In linux kernel since version 3.12 (release Date: 2013-11-03)  
Use reference implementation of APE6EVM board support
which makes a greater use of device tree at the expense
of not supporting a number of devices.

This is intended to aid developers

source code: