Fix rocksmq bug

Signed-off-by: groot <yihua.mo@zilliz.com>

internal/msgstream/rmqms/rmq_msgstream.go

@@ -103,6 +103,9 @@ func (ms *RmqMsgStream) AsProducer(channels []string) {
 		err := rocksmq.Rmq.CreateChannel(channel)
 		if err == nil {
 			ms.producers = append(ms.producers, channel)
+		} else {
+			errMsg := "Failed to create producer " + channel + ", error = " + err.Error()
+			panic(errMsg)
 		}
 	}
 }

internal/util/rocksmq/rocksmq.go

@@ -128,7 +128,7 @@ func (rmq *RocksMQ) CreateChannel(channelName string) error {
 
 	// Check if channel exist
 	if rmq.checkKeyExist(beginKey) || rmq.checkKeyExist(endKey) {
-		return errors.New("Channel " + channelName + " already exists.")
+		return nil
 	}
 
 	err := rmq.kv.Save(beginKey, "0")