omap2420-h4: Add device tree support

Enable device-tree support for the omap2420-h4 board.
Signed-off-by: NJon Hunter <jon-hunter@ti.com>

include/configs/omap2420h4.h

@@ -67,6 +67,7 @@
 #define CONFIG_SETUP_MEMORY_TAGS 1
 #define CONFIG_INITRD_TAG        1
 #define CONFIG_REVISION_TAG      1
+#define CONFIG_OF_LIBFDT
 
 /*
  * Size of malloc() pool