CONFIG_BOARD_ATSTK1000 is not available for the selected architecture x86.
Result is shown for architecture avr32

ATSTK1000 evaluation board

configname: CONFIG_BOARD_ATSTK1000

AVR32 board type
└─>ATSTK1000 evaluation board
In linux kernel since version 2.6.19 (release Date: 2006-11-29)