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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REL9_1_STABLE

Details
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http://git.postgresql.org/pg/commitdiff/6d362ec209f0174f36a78936c5269f8d5f2cd26e

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