Rework DHCP lease state handling to be compatible with failover protocol.

includes/failover.h

@@ -157,13 +157,17 @@ typedef struct {
 #define FTR_UNKNOWN		254
 
 /* Lease states: */
-#define FTS_FREE		1
-#define FTS_ACTIVE		2
-#define FTS_EXPIRED		3
-#define FTS_RELEASED		4
-#define FTS_ABANDONED		5
-#define FTS_RESET		6
-#define FTS_BACKUP		7
+typedef enum {
+	FTS_FREE = 1,
+	FTS_ACTIVE = 2,
+	FTS_EXPIRED = 3,
+	FTS_RELEASED = 4,
+	FTS_ABANDONED = 5,
+	FTS_RESET = 6,
+	FTS_BACKUP = 7,
+	FTS_RESERVED = 8,
+	FTS_BOOTP = 9
+} binding_state_t;
 
 #define DHCP_FAILOVER_MAX_MESSAGE_SIZE	2048