CONFIG_MACH_SMDKC210 is not available for thedefaultarchitecture x86.
Result is shown for architecture arm
SMDKC210
modulename: mach-smdkc210.ko
configname: CONFIG_MACH_SMDKC210
Linux Kernel Configuration
└─>EXYNOS4 Machines
└─>SMDKC210
In linux kernel since version 2.6.37 (release Date: 2011-01-04)
Machine support for Samsung SMDKC210