[AVR32] Make STK1000 mux settings configurable

This adds some STK1002-specific config options covering the jumper settings,
so the kernel can automatically be configured to include the relevant devices.

One of them replaces the previous internal SW2_DEFAULT setting; SPI config
is affected by two of the jumpers; and a fourth one switches between LCD and
the second Ethernet connector.  (There's more that to be done.)

Signed-off-by: David Brownell <dbrownell@users.sourceforge.net>
Signed-off-by: Haavard Skinnemoen <hskinnemoen@atmel.com>
diff --git a/arch/avr32/Kconfig b/arch/avr32/Kconfig
index 8f37a14..d12346a 100644
--- a/arch/avr32/Kconfig
+++ b/arch/avr32/Kconfig
@@ -113,6 +113,10 @@
 	bool "ATNGW100 Network Gateway"
 endchoice
 
+if BOARD_ATSTK1000
+source "arch/avr32/boards/atstk1000/Kconfig"
+endif
+
 choice
 	prompt "Boot loader type"
 	default LOADER_U_BOOT