pgsql: Remove link to ODBCng project from the docs.

Remove link to ODBCng project from the docs.

This backatches Heikki's patch in 140a4fbf1a87891a79a2c61a08416828d39f286a
to make sure the documentation on the website gets updated, since
we're regularly receiving complains about this link.

Branch
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REL8_4_STABLE

Details
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http://git.postgresql.org/pg/commitdiff/56c8d50eaf4683049c07e0ed75747615f021a3b1

Modified Files
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doc/src/sgml/external-projects.sgml |    9 +--------
1 files changed, 1 insertions(+), 8 deletions(-)