CONFIG_BOARD_ATSTK1006 is not available for thedefaultarchitecture x86.
Result is shown for architecture avr32
default or selected kernelversion does not have config value CONFIG_BOARD_ATSTK1006.
Result is shown for kernelversion 6.5.1

ATSTK1006

modulename: atstk1002.ko

configname: CONFIG_BOARD_ATSTK1006

ATSTK1000 CPU daughterboard type
└─>ATSTK1006
In linux kernel since version 2.6.27 (release Date: 2008-10-09)  
source code:
arch/avr32/boards/atstk1000/atstk1002.c