CONFIG_MACH_SMDK4412 is not available for thedefaultarchitecture x86.
Result is shown for architecture arm
SMDK4412
modulename: mach-smdk4x12.ko
configname: CONFIG_MACH_SMDK4412
Linux Kernel Configuration
└─>SAMSUNG EXYNOS SoCs Support
└─>SMDK4412
In linux kernel since version 3.1 (release Date: 2011-10-24)
Machine support for Samsung SMDK4412