CONFIG_MACH_EDB9312 is not available for thedefaultarchitecture x86.
Result is shown for architecture arm

Support Cirrus Logic EDB9312

modulename: edb9312.ko

configname: CONFIG_MACH_EDB9312

Linux Kernel Configuration
└─>Cirrus EP93xx Implementation Options
└─>Support Cirrus Logic EDB9312
In linux kernel since version 2.6.19 (release Date: 2006-11-29)  
Say 'Y' here if you want your kernel to support the Cirrus
Logic EDB9312 Evaluation Board.

source code:
arch/arm/mach-ep93xx/edb9312.c