pgsql: Fix ruleutils to print "INSERT INTO foo DEFAULT VALUES" correctl

Fix ruleutils to print "INSERT INTO foo DEFAULT VALUES" correctly.

Per bug #7615 from Marko Tiikkaja. Apparently nobody ever tried this
case before ...

Branch
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master

Details
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http://git.postgresql.org/pg/commitdiff/0d6895051a2e53026ad0daae0ebc3cb901acc521

Modified Files
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src/backend/utils/adt/ruleutils.c | 18 +++++++++++++-----
1 files changed, 13 insertions(+), 5 deletions(-)