powerpc/85xx: Enable Errata command on MPC8572DS

Also removed duplicate CONFIG_CMD_IRQ define.

Signed-off-by: York Sun <yorksun@freescale.com>
Signed-off-by: Kumar Gala <galak@kernel.crashing.org>

include/configs/MPC8572DS.h

@@ -654,12 +654,12 @@
  */
 #include <config_cmd_default.h>
 
+#define CONFIG_CMD_ERRATA
 #define CONFIG_CMD_IRQ
 #define CONFIG_CMD_PING
 #define CONFIG_CMD_I2C
 #define CONFIG_CMD_MII
 #define CONFIG_CMD_ELF
-#define CONFIG_CMD_IRQ
 #define CONFIG_CMD_SETEXPR
 #define CONFIG_CMD_REGINFO