pgsql: Update xindex.sgml for recent additions to GIST opclass API.

Update xindex.sgml for recent additions to GIST opclass API.

Commit d04c8ed9044ec added another support function to the GIST API,
but overlooked mentioning it in xindex.sgml's summary of index support
functions.

Anastasia Lubennikova

Branch
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master

Details
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http://git.postgresql.org/pg/commitdiff/b0cfb02cec9650492365c6a9eca2dfce3671096d

Modified Files
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doc/src/sgml/xindex.sgml |   14 ++++++++++----
1 file changed, 10 insertions(+), 4 deletions(-)