Template:Submittinginfo
Register on the forum (if you aren't already registered) and once your account has been activated, post the info in the "New Dumps & Redumps" sub-forum. Or if this is a one-off submission, you can use one of the other contact methods listed on the main page.
Or if you have a login for it, you can submit the dump info directly to the DAT-o-MATIC database.
Note: DAT-o-MATIC supports importing XMLs in this format directly: https://datomatic.no-intro.org/stuff/example_upload_custom.xml, although there isn't a proper specification (or tool to generate this format from folder(s)/file(s)) yet