kconfig: add board Kconfig and defconfig files

This commit adds:
 - arch/${ARCH}/Kconfig
    provide a menu to select target boards
 - board/${VENDOR}/${BOARD}/Kconfig or board/${BOARD}/Kconfig
    set CONFIG macros to the appropriate values for each board
 - configs/${TARGET_BOARD}_defconfig
    default setting of each board

(This commit was automatically generated by a conversion script
based on boards.cfg)

In Linux Kernel, defconfig files are located under
arch/${ARCH}/configs/ directory.
It works in Linux Kernel since ARCH is always given from the
command line for cross compile.

But in U-Boot, ARCH is not given from the command line.
Which means we cannot know ARCH until the board configuration is done.
That is why all the "*_defconfig" files should be gathered into a
single directory ./configs/.

Signed-off-by: Masahiro Yamada <yamada.m@jp.panasonic.com>
Acked-by: Simon Glass <sjg@chromium.org>
diff --git a/arch/avr32/Kconfig b/arch/avr32/Kconfig
new file mode 100644
index 0000000..46337ae
--- /dev/null
+++ b/arch/avr32/Kconfig
@@ -0,0 +1,51 @@
+menu "AVR32 architecture"
+	depends on AVR32
+
+config SYS_ARCH
+	string
+	default "avr32"
+
+choice
+	prompt "Target select"
+
+config TARGET_ATNGW100
+	bool "Support atngw100"
+
+config TARGET_ATNGW100MKII
+	bool "Support atngw100mkii"
+
+config TARGET_ATSTK1002
+	bool "Support atstk1002"
+
+config TARGET_ATSTK1003
+	bool "Support atstk1003"
+
+config TARGET_ATSTK1004
+	bool "Support atstk1004"
+
+config TARGET_ATSTK1006
+	bool "Support atstk1006"
+
+config TARGET_FAVR_32_EZKIT
+	bool "Support favr-32-ezkit"
+
+config TARGET_GRASSHOPPER
+	bool "Support grasshopper"
+
+config TARGET_MIMC200
+	bool "Support mimc200"
+
+config TARGET_HAMMERHEAD
+	bool "Support hammerhead"
+
+endchoice
+
+source "board/atmel/atngw100/Kconfig"
+source "board/atmel/atngw100mkii/Kconfig"
+source "board/atmel/atstk1000/Kconfig"
+source "board/earthlcd/favr-32-ezkit/Kconfig"
+source "board/in-circuit/grasshopper/Kconfig"
+source "board/mimc/mimc200/Kconfig"
+source "board/miromico/hammerhead/Kconfig"
+
+endmenu