[t:4762], fix memory leak

git-svn-id: file:///svn/toku/tokudb@42337 c7de825b-a66e-492c-adef-691d508d4ae1

newbrt/brt.c

@@ -2467,6 +2467,7 @@ toku_bnc_flush_to_child(
 
         // Free the OMT's we used for garbage collecting.
         toku_omt_destroy(&snapshot_txnids);
+        toku_omt_destroy(&live_root_txns);
         toku_omt_free_items_pool(live_list_reverse);
         toku_omt_destroy(&live_list_reverse);
     }