pgsql: docs: Clarify pg_ctl initdb option text to match options proto.

docs: Clarify pg_ctl initdb option text to match options proto.

The options string appeared in PG 10.

Reported-by: pgsql-kr@postgresql.kr

Discussion: /messages/by-id/153500377658.1378.6587007319641704057@wrigleys.postgresql.org

Backpatch-through: 10

Branch
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REL_10_STABLE

Details
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https://git.postgresql.org/pg/commitdiff/dfd840f105506db988566436c1559866bd73ab55

Modified Files
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doc/src/sgml/ref/pg_ctl-ref.sgml | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)