CONFIG_SOC_EXYNOS5440 is not available for thedefaultarchitecture x86.
Result is shown for architecture arm
SAMSUNG EXYNOS5440
configname: CONFIG_SOC_EXYNOS5440
Linux Kernel Configuration
└─>SAMSUNG EXYNOS SoCs Support
└─>SAMSUNG EXYNOS5440
In linux kernel since version 3.1 (release Date: 2011-10-24)
Enable EXYNOS5440 SoC support