After 0.12 version, doris remove the format convert functiion which can convert from hdr_ format
to tabletmeta_ format when loading metas, the commit link: 3bca253
When we update doris version and there are old format meta in storage,
BE will not read the old format tablet. It can lead to data loss.
So we add meta format detection function to prevent data loss.
When there are old format meta in olap_meta, BE can find and print log or exit.
4571b09dd6