[AVR32] Kconfig: Choose daughterboard instead of CPU

Remove the CPU selection menu and instead let it be selected by the
board or daughterboard option. Add daughterboard selection for
ATSTK1000 (this was previously determined based on CPU type.)

Signed-off-by: Haavard Skinnemoen <hskinnemoen@atmel.com>
diff --git a/arch/avr32/boards/atstk1000/Kconfig b/arch/avr32/boards/atstk1000/Kconfig
index 28c4780..af90b00 100644
--- a/arch/avr32/boards/atstk1000/Kconfig
+++ b/arch/avr32/boards/atstk1000/Kconfig
@@ -2,6 +2,25 @@
 
 if BOARD_ATSTK1000
 
+choice
+	prompt "ATSTK1000 CPU daughterboard type"
+	default BOARD_ATSTK1002
+
+config BOARD_ATSTK1002
+	bool "ATSTK1002"
+	select CPU_AT32AP7000
+
+config BOARD_ATSTK1003
+	bool "ATSTK1003"
+	select CPU_AT32AP7001
+
+config BOARD_ATSTK1004
+	bool "ATSTK1004"
+	select CPU_AT32AP7002
+
+endchoice
+
+
 config BOARD_ATSTK100X_CUSTOM
 	bool "Non-default STK1002/STK1003/STK1004 jumper settings"
 	help