CONFIG_CPU_EXYNOS4210 is not available for thedefaultarchitecture x86.
Result is shown for architecture arm

CONFIG_CPU_EXYNOS4210 (not configurable)

modulename: setup-i2c0.ko

and/or

cpu.ko

configname: CONFIG_CPU_EXYNOS4210

Linux Kernel Configuration
└─>CPU_EXYNOS4210
In linux kernel since version 2.6.39 (release Date: 2011-05-18)  
Enable EXYNOS4210 CPU support

source code:

depends
CONFIG_ARCH_EXYNOS4 or &

is selected by
CONFIG_SERIAL_S5PV210

is depended by
CONFIG_ARCH_EXYNOS4