Avoid redo log parsing during backup

Redo parsing during backup. Because of this parsing, we cannot copy the redo file as fast as we can.

This can be avoided for the new layout design. ie we should just copy redo as chunks/files without worrying about parsing redo. Current users of redo parsing during backup.

1.  

   1. Look for DDL that skipped redo and happened during backup (lock-ddl=false) MLOG_INDEX_LOAD

   2. Encrypted tablespace that were just created before backup. ie Page 0 doesn't have encryption info

   3. The use-memory feature that predicts the amount of redo

   4. Find the end of redo to be copied. (From 8.0, we now use pfs.log_status table to find the desired LSN to stop)