etcdserver: log auto compaction on server start

Signed-off-by: Gyuho Lee <gyuhox@gmail.com>

etcdserver/config.go

@@ -273,6 +273,8 @@ func (c *ServerConfig) print(initial bool) {
 			zap.Bool("pre-vote", c.PreVote),
 			zap.Bool("initial-corrupt-check", c.InitialCorruptCheck),
 			zap.Duration("corrupt-check-time", c.CorruptCheckTime),
+			zap.String("auto-compaction-mode", c.AutoCompactionMode),
+			zap.Duration("auto-compaction-retention", c.AutoCompactionRetention),
 			zap.String("discovery-url", c.DiscoveryURL),
 			zap.String("discovery-proxy", c.DiscoveryProxy),
 		)