mx53loco: Allow booting a zImage kernel

Allow booting a zImage kernel.

Signed-off-by: Fabio Estevam <fabio.estevam@freescale.com>
diff --git a/include/configs/mx53loco.h b/include/configs/mx53loco.h
index 9e8f5ce..f2384f3 100644
--- a/include/configs/mx53loco.h
+++ b/include/configs/mx53loco.h
@@ -104,6 +104,7 @@
 
 /* Command definition */
 #include <config_cmd_default.h>
+#define CONFIG_CMD_BOOTZ
 
 #undef CONFIG_CMD_IMLS