relnotes: clarify pg_basebackup compression options

Bruce Momjian <bruce@momjian.us>

Commit: 795ccd44037cbe14a7366d90de94764a7136deb7
Author: Bruce Momjian <bruce@momjian.us>
Date: 2022-07-19T20:45:25Z
Releases: 15.0
relnotes:  clarify pg_basebackup compression options

Also, a few wording improvements

Reported-by: Justin Pryzby

Discussion: https://postgr.es/m/20220719181307.GG12702@telsasoft.com

Backpatch-through: 15 only

Files

PathChange+/−
doc/src/sgml/release-15.sgml modified +28 −19

Documentation touched