CONFIG_MACH_AT91SAM9G10EK is not available for thedefaultarchitecture x86.
Result is shown for architecture arm

Atmel AT91SAM9G10-EK Evaluation Kit

modulename: board-sam9261ek.ko

configname: CONFIG_MACH_AT91SAM9G10EK

Linux Kernel Configuration
└─>Atmel Non-DT world
└─>Atmel AT91SAM9G10-EK Evaluation Kit
In linux kernel since version 2.6.32 (release Date: 2009-12-02)  
Select this if you are using Atmel's AT91SAM9G10-EK Evaluation Kit.
<http://www.atmel.com/dyn/products/tools_card.asp?tool_id=4588>

source code: