fix some coredump

source/dnode/vnode/src/tsdb/tsdbDataFileRW.c

@@ -1209,7 +1209,7 @@ _exit:
 }
 
 static int32_t tsdbDataFileDoWriteTombBlk(SDataFileWriter *writer) {
-  ASSERT(TARRAY2_SIZE(writer->tombBlkArray) == 0);
+  ASSERT(TARRAY2_SIZE(writer->tombBlkArray) > 0);
 
   int32_t code = 0;
   int32_t lino = 0;

source/dnode/vnode/src/tsdb/tsdbIter.c

@@ -613,6 +613,8 @@ int32_t tsdbIterNext(STsdbIter *iter) {
       return tsdbSttTombIterNext(iter, NULL);
     case TSDB_ITER_TYPE_DATA_TOMB:
       return tsdbDataTombIterNext(iter, NULL);
+    case TSDB_ITER_TYPE_MEMT_TOMB:
+      return tsdbMemTombIterNext(iter, NULL);
     default:
       ASSERT(false);
   }