CONFIG_MACH_SMDK2416 is not available for thedefaultarchitecture x86.
Result is shown for architecture arm

SMDK2416

modulename: mach-smdk2416.ko

and/or

configname: CONFIG_MACH_SMDK2416

Linux Kernel Configuration
└─>Samsung S3C24XX SoCs Support
└─>SMDK2416
In linux kernel since version 2.6.35 (release Date: 2010-08-01)  
Say Y here if you are using an SMDK2416