CONFIG_GUMSTIX_AM300EPD is not available for thedefaultarchitecture x86.
Result is shown for architecture arm

Enable AM300EPD board support

modulename: am300epd.ko

configname: CONFIG_GUMSTIX_AM300EPD

Gumstix Carrier/Expansion Board
└─>Enable AM300EPD board support
In linux kernel since version 2.6.30 (release Date: 2009-06-09)  
source code:
arch/arm/mach-pxa/am300epd.c