Adapt sourceforge lister to list cvs origins according to what the cvs loader expects

The actual listing [1] won't currently work given how the loader cvs consumes origins.

16:00 <stsp> the urls given there won't work
16:01 <stsp> the lister needs to know how sf.net exposes its cvs repositories (pserver and/or rsync; pserver will definitely be supported since that it what cvs clients are using)
16:02 <stsp> another option is anonymou ssh, which is like pserver but authenticated so should be preferred if available

• [1] swh/meta$1232

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Migrated from T3789 (view on Phabricator)