CONFIG_S3C_DEV_I2C6 is not available for thedefaultarchitecture x86.
Result is shown for architecture arm
default or selected kernelversion does not have config value CONFIG_S3C_DEV_I2C6.
Result is shown for kernelversion 6.9.9

CONFIG_S3C_DEV_I2C6 (not configurable)

configname: CONFIG_S3C_DEV_I2C6

Linux Kernel Configuration
└─>Samsung Common options
└─>S3C_DEV_I2C6
In linux kernel since version 2.6.37 (release Date: 2011-01-04)  
Compile in platform device definition for I2C controller 6