CONFIG_MACH_ARMADILLO800EVA_REFERENCE is not available for thedefaultarchitecture x86.
Result is shown for architecture arm

Armadillo-800 EVA board - Reference Device Tree Implementation

modulename: board-armadillo800eva-reference.ko

configname: CONFIG_MACH_ARMADILLO800EVA_REFERENCE

Linux Kernel Configuration
└─>Armadillo-800 EVA board - Reference Device Tree Implementation
In linux kernel since version 3.11 (release Date: 2013-09-02)  
Use reference implementation of Armadillo800 EVA board support
which makes greater use of device tree at the expense
of not supporting a number of devices.

This is intended to aid developers

source code: