CONFIG_MACH_NEOCORE926 is not available for thedefaultarchitecture x86.
Result is shown for architecture arm

Adeneo NEOCORE926

modulename: board-neocore926.ko

configname: CONFIG_MACH_NEOCORE926

Linux Kernel Configuration
└─>Atmel AT91 System-on-Chip
└─>Adeneo NEOCORE926
In linux kernel since version 2.6.29 (release Date: 2009-03-23)  
Select this if you are using the Adeneo Neocore 926 board.

source code: