CONFIG_CPU_FREQ_S3C24XX is not available for thedefaultarchitecture x86.
Result is shown for architecture arm

CPUfreq driver for Samsung S3C24XX series CPUs (EXPERIMENTAL)

modulename: cpu-freq.ko

configname: CONFIG_CPU_FREQ_S3C24XX

Linux Kernel Configuration
└─>CPU Power Management
└─>CPUfreq driver for Samsung S3C24XX series CPUs (EXPERIMENTAL)
In linux kernel since version 2.6.32 (release Date: 2009-12-02)  
This enables the CPUfreq driver for the Samsung S3C24XX family
of CPUs.

For details, take a look at Documentation/cpu-freq.

If in doubt, say N.

source code:

depends
CONFIG_ARCH_HAS_CPUFREQ
CONFIG_ARCH_S3C2410
CONFIG_CPU_FREQ
CONFIG_EXPERIMENTAL