CONFIG_MACH_AT2440EVB is not available for thedefaultarchitecture x86.
Result is shown for architecture arm

Avantech AT2440EVB development board

modulename: mach-at2440evb.ko

and/or

configname: CONFIG_MACH_AT2440EVB

Linux Kernel Configuration
└─>Samsung S3C24XX SoCs (deprecated, see help)
└─>Samsung S3C24XX SoCs Support
└─>Avantech AT2440EVB development board
In linux kernel since version 2.6.27 (release Date: 2008-10-09)  
Say Y here if you are using the AT2440EVB development board