pgsql: Fix backwards logic in previous commit.

Fix backwards logic in previous commit.

I wrote this code before committing it, but managed not to include it in
the actual commit.

Branch
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master

Details
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http://git.postgresql.org/pg/commitdiff/df970a0ac8fb416b179825a135c18ad3293076af

Modified Files
--------------
src/backend/commands/tablecmds.c |   11 ++++++-----
1 files changed, 6 insertions(+), 5 deletions(-)