CONFIG_S3C24XX_SIMTEC_PM is not available for thedefaultarchitecture x86.
Result is shown for architecture arm

CONFIG_S3C24XX_SIMTEC_PM (not configurable)

modulename: simtec-pm.ko

configname: CONFIG_S3C24XX_SIMTEC_PM

Linux Kernel Configuration
└─>SAMSUNG S3C24XX SoCs Support
└─>S3C24XX_SIMTEC_PM
In linux kernel since version 3.1 (release Date: 2011-10-24)  
Common power management code for systems that are
compatible with the Simtec style of power management

source code:
arch/arm/mach-s3c24xx/simtec-pm.c