CONFIG_MACH_AT91SAM9M10G45EK is not available for thedefaultarchitecture x86.
Result is shown for architecture arm
default or selected kernelversion does not have config value CONFIG_MACH_AT91SAM9M10G45EK.
Result is shown for kernelversion 6.5.1

Atmel AT91SAM9M10G45-EK Evaluation Kits

modulename: board-sam9m10g45ek.ko

configname: CONFIG_MACH_AT91SAM9M10G45EK

Linux Kernel Configuration
└─>Atmel Non-DT world
└─>Atmel AT91SAM9M10G45-EK Evaluation Kits
In linux kernel since version 2.6.37 (release Date: 2011-01-04)  
Select this if you are using Atmel's AT91SAM9M10G45-EK Evaluation Kit.
Those boards can be populated with any SoC of AT91SAM9G45 or AT91SAM9M10
families: AT91SAM9G45, AT91SAM9G46, AT91SAM9M10 and AT91SAM9M11.
<http://www.atmel.com/tools/SAM9M10-G45-EK.aspx>

source code: