pgsql: Doc: Improve readability of options for REINDEX

Doc: Improve readability of options for REINDEX

That's more consistent with the style we have been using with for
example EXPLAIN, VACUUM or ANALYZE (this one had only one option in
v11).  Based on a suggestion from Pavel Stehule.

Author: Josef Šimánek
Discussion: https://postgr.es/m/CAFj8pRCrUS+eMFvssVPGZN-VDEMP3XN+1Dop0=CmeBq2D+dqOg@mail.gmail.com
Discussion: https://postgr.es/m/CAFp7QwpeMPEtAR5AYpsG623ooMWX03wMjq5cpZn=X+6OCkfwJw@mail.gmail.com

Branch
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master

Details
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https://git.postgresql.org/pg/commitdiff/52dcfda48778d16683c64ca4372299a099a15b96

Modified Files
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doc/src/sgml/ref/reindex.sgml | 6 +++++-
1 file changed, 5 insertions(+), 1 deletion(-)