mx31pdk: Change the prompt as per other i.MX boards

Change the prompt as done in other i.MX boards.

Signed-off-by: Fabio Estevam <fabio.estevam@freescale.com>

include/configs/mx31pdk.h

@@ -124,7 +124,7 @@
  * Miscellaneous configurable options
  */
 #define CONFIG_SYS_LONGHELP	/* undef to save memory */
-#define CONFIG_SYS_PROMPT	"uboot> "
+#define CONFIG_SYS_PROMPT	"MX31PDK U-Boot > "
 #define CONFIG_SYS_CBSIZE	256	/* Console I/O Buffer Size */
 /* Print Buffer Size */
 #define CONFIG_SYS_PBSIZE	(CONFIG_SYS_CBSIZE + \