pgsql: Doc: remove obsolete comment.

Doc: remove obsolete comment. This para should have been removed by 2f9661311, which made it both false and irrelevant. Noted while looking at SQL function plancache patch. Branch -- master Details --- https://git.postgresql.org/pg/commitdiff/1c9242b2cdc358b8be9c4e9967823a24a7807525 Mo

pgsql: Doc: remove obsolete comment about per-branch documentation.

Doc: remove obsolete comment about per-branch documentation. I should have removed this in a0b762626, but forgot. Branch -- master Details --- https://git.postgresql.org/pg/commitdiff/8309eae499d6782bfc5e81f4d1cfcbf8e3fc8f5d Modified Files -- doc/src/sgml/release.sgml | 3 +-