m28evk: Allow to booting a dt kernel

Allow to booting a dt kernel.

Signed-off-by: Fabio Estevam <fabio.estevam@freescale.com>
diff --git a/include/configs/m28evk.h b/include/configs/m28evk.h
index 012381a..39d6a07 100644
--- a/include/configs/m28evk.h
+++ b/include/configs/m28evk.h
@@ -279,6 +279,7 @@
 #define	CONFIG_BOOTCOMMAND	"run bootcmd_net"
 #define	CONFIG_LOADADDR		0x42000000
 #define	CONFIG_SYS_LOAD_ADDR	CONFIG_LOADADDR
+#define	CONFIG_OF_LIBFDT
 
 /*
  * Extra Environments