pgsql: Tweak documentation wording to avoid "pdfendlink" failure.

Tweak documentation wording to avoid "pdfendlink" failure.

HEAD documentation was failing to build as US PDF for me, because a link
to "CREATE CAST" was getting split across pages. Adjust wording to
remove this rather gratuitous cross-reference.

Branch
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master

Details
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http://git.postgresql.org/pg/commitdiff/e3cdc1532caaec4652b41d1114c71aa3872a8f6f

Modified Files
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doc/src/sgml/catalogs.sgml | 3 +--
1 files changed, 1 insertions(+), 2 deletions(-)