fix missing mutex-unlock call in few files.

[TD-121]

src/client/src/tscServer.c

@@ -1787,6 +1787,7 @@ int tscBuildHeartBeatMsg(SSqlObj *pSql, SSqlInfo *pInfo) {
 
   size = tscEstimateHeartBeatMsgLength(pSql);
   if (TSDB_CODE_SUCCESS != tscAllocPayload(pCmd, size)) {
+    pthread_mutex_unlock(&pObj->mutex);
     tscError("%p failed to malloc for heartbeat msg", pSql);
     return -1;
   }

src/client/src/tscSubquery.c

@@ -1381,6 +1381,7 @@ static void tscRetrieveFromDnodeCallBack(void *param, TAOS_RES *tres, int numOfR
   } else { // all data has been retrieved to client
     tscAllDataRetrievedFromDnode(trsupport, pSql);
   }
+  pthread_mutex_unlock(&trsupport->queryMutex);
 }
 
 static SSqlObj *tscCreateSqlObjForSubquery(SSqlObj *pSql, SRetrieveSupport *trsupport, SSqlObj *prevSqlObj) {

src/mnode/src/mgmtSdb.c

@@ -695,6 +695,7 @@ int32_t sdbUpdateRow(SSdbOperDesc *pOper) {
   int32_t total_size = sizeof(SRowHead) + pTable->maxRowSize + sizeof(TSCKSUM);
   SRowHead *rowHead = (SRowHead *)calloc(1, total_size);
   if (rowHead == NULL) {
+    pthread_mutex_unlock(&pTable->mutex);
     sdbError("table:%s, failed to allocate row head memory", pTable->tableName);
     return -1;
   }