CONFIG_MACH_SAM9_L9260 is not available for thedefaultarchitecture x86.
Result is shown for architecture arm

Olimex SAM9-L9260 board

modulename: board-sam9-l9260.ko

configname: CONFIG_MACH_SAM9_L9260

Linux Kernel Configuration
└─>Atmel AT91 System-on-Chip
└─>Olimex SAM9-L9260 board
In linux kernel since version 2.6.26 (release Date: 2008-07-13)  
Select this if you are using Olimex's SAM9-L9260 board based on the Atmel AT91SAM9260.
<http://www.olimex.com/dev/sam9-L9260.html>

source code:
arch/arm/mach-at91/board-sam9-l9260.c