CONFIG_SA1100_ASSABET is not available for thedefaultarchitecture x86.
Result is shown for architecture arm

Assabet

modulename: assabet.ko

configname: CONFIG_SA1100_ASSABET

Linux Kernel Configuration
└─>SA11x0 Implementations
└─>Assabet
In linux kernel since version 2.6.12  
Say Y here if you are using the Intel(R) StrongARM(R) SA-1110
Microprocessor Development Board (also known as the Assabet).

source code:
arch/arm/mach-sa1100/assabet.c


is selected by
CONFIG_ASSABET_NEPONSET