arm: am335x: Add DT (FDT) support to Siemens boards

Enable FDT support for all Siemens AM335x boards. To support
newer Linux kernels with DT booting.

Signed-off-by: Stefan Roese <sr@denx.de>
Cc: Heiko Schocher <hs@denx.de>
Cc: Roger Meier <r.meier@siemens.com>
Cc: Lukas Stockmann <lukas.stockmann@siemens.com>
Cc: Tom Rini <trini@ti.com>
Acked-by: Heiko Schocher<hs@denx.de>

include/configs/siemens-am33x-common.h

@@ -487,4 +487,9 @@
 
 #define CONFIG_BOOTCOUNT_LIMIT
 #define CONFIG_BOOTCOUNT_ENV
+
+/* Enable Device-Tree (FDT) support */
+#define CONFIG_OF_LIBFDT
+#define CONFIG_CMD_FDT
+
 #endif	/* ! __CONFIG_SIEMENS_AM33X_COMMON_H */