pgsql: Put back gistgettuple's check for backwards scan request.

Put back gistgettuple's check for backwards scan request.

On reflection it's a bad idea for the KNNGIST patch to have removed that.
We don't want it silently returning incorrect answers.

Branch
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master

Details
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http://git.postgresql.org/gitweb?p=postgresql.git;a=commitdiff;h=04910a3ad5cd2901558da2a4fad9a2e2819348aa

Modified Files
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src/backend/access/gist/gistget.c |    4 ++++
1 files changed, 4 insertions(+), 0 deletions(-)