CONFIG_S3C64XX_SETUP_KEYPAD is not available for thedefaultarchitecture x86.
Result is shown for architecture arm

CONFIG_S3C64XX_SETUP_KEYPAD (not configurable)

configname: CONFIG_S3C64XX_SETUP_KEYPAD

Linux Kernel Configuration
└─>Samsung S3C64XX (deprecated, see help)
└─>S3C64XX_SETUP_KEYPAD
In linux kernel since version 2.6.36 (release Date: 2010-10-20)  
Common setup code for S3C64XX KEYPAD GPIO configurations