pgsql: Avoid generating excess (and illegal) parentheses around an

Log Message:
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Avoid generating excess (and illegal) parentheses around an aliased JOIN
in prettyprint mode. Andreas Pflug

Modified Files:
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pgsql/src/backend/utils/adt:
ruleutils.c (r1.186 -> r1.187)
(http://developer.postgresql.org/cvsweb.cgi/pgsql/src/backend/utils/adt/ruleutils.c.diff?r1=1.186&r2=1.187)