Mention MDB_PREV_MULTIPLE along with MDB_NEXT_MULTIPLE

libraries/liblmdb/lmdb.h

@@ -1140,8 +1140,9 @@ int  mdb_txn_renew(MDB_txn *txn);
 	 *		This flag may only be used in combination with #MDB_DUPSORT. This option
 	 *		tells the library that the data items for this database are all the same
 	 *		size, which allows further optimizations in storage and retrieval. When
-	 *		all data items are the same size, the #MDB_GET_MULTIPLE and #MDB_NEXT_MULTIPLE
-	 *		cursor operations may be used to retrieve multiple items at once.
+	 *		all data items are the same size, the #MDB_GET_MULTIPLE, #MDB_NEXT_MULTIPLE
+	 *		and #MDB_PREV_MULTIPLE cursor operations may be used to retrieve multiple
+	 *		items at once.
 	 *	<li>#MDB_INTEGERDUP
 	 *		This option specifies that duplicate data items are binary integers,
 	 *		similar to #MDB_INTEGERKEY keys.