CONFIG_MACH_MX25_3DS is not available for thedefaultarchitecture x86.
Result is shown for architecture arm

Support MX25PDK (3DS) Platform

modulename: mx25pdk.ko

configname: CONFIG_MACH_MX25_3DS

Linux Kernel Configuration
└─>Support MX25PDK (3DS) Platform
In linux kernel since version 2.6.32 (release Date: 2009-12-02)  
source code:
arch/arm/mach-mx25/mx25pdk.c