add RTC control command

git-svn-id: https://rt-thread.googlecode.com/svn/trunk@2377 bbd45198-f89e-11dd-88c7-29a3b14d5316

include/rtdef.h

@@ -694,7 +694,9 @@ enum rt_device_class_type
 #define RT_DEVICE_CTRL_NETIF_GETMAC     0x10            /**< get mac address */
 #define RT_DEVICE_CTRL_MTD_FORMAT       0x10            /**< format a MTD device */
 #define RT_DEVICE_CTRL_RTC_GET_TIME     0x10            /**< get time */
-#define RT_DEVICE_CTRL_RTC_SET_TIME     0x11            /**< set time */
+#define RT_DEVICE_CTRL_RTC_SET_TIME     0x11            /**< set time */
+#define RT_DEVICE_CTRL_RTC_GET_ALARM    0x12            /**< get alarm */
+#define RT_DEVICE_CTRL_RTC_SET_ALARM    0x13            /**< set alarm */
 
 typedef struct rt_device *rt_device_t;
 /**