pgsql: Invert and rename flag variable to improve code readability.

Invert and rename flag variable to improve code readability.

No change in functionality. Per discussion with Robert.

Branch
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master

Details
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http://git.postgresql.org/gitweb?p=postgresql.git;a=commitdiff;h=39c8dd66204ebfea9c1c6a7a9ca38b7419dbe8a1

Modified Files
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src/backend/optimizer/path/joinpath.c | 47 +++++++++++++++++----------------
1 files changed, 24 insertions(+), 23 deletions(-)