pgsql: Tidy up a few cosmetic issues related to pg_basebackup.

Tidy up a few cosmetic issues related to pg_basebackup.

Commit 0ad8032910d5eb8efd32867c45b6a25c85e60f50 failed to update
the pg_basebackup documentation to mention that "client-" or
"server-" can now be prepended to the compression method name. Fix
it there, and also in the --help output that you get from running
the binary.

Also in the documentation, there's an old issue that the arguments to
--checkpoint shouldn't be marked as parameters, because "fast" and
"spread" are literal strings. Fix that too.

Dagfinn Ilmari Mannsåker, partly as per a report from
Shinoda Noriyoshi.

Discussion: http://postgr.es/m/PH7PR84MB1885C1CF433057807551172BEE5F9@PH7PR84MB1885.NAMPRD84.PROD.OUTLOOK.COM

Branch
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master

Details
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https://git.postgresql.org/pg/commitdiff/e1f860f13459e186479319aa9f65ef184277805f

Modified Files
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doc/src/sgml/ref/pg_basebackup.sgml | 8 ++++----
src/bin/pg_basebackup/pg_basebackup.c | 2 +-
2 files changed, 5 insertions(+), 5 deletions(-)