pgsql: Fix inline_set_returning_function() to allow multiple OUT parame

Fix inline_set_returning_function() to allow multiple OUT parameters.

inline_set_returning_function failed to distinguish functions returning
generic RECORD (which require a column list in the RTE, as well as run-time
type checking) from those with multiple OUT parameters (which do not).
This prevented inlining from happening. Per complaint from Jay Levitt.
Back-patch to 8.4 where this capability was introduced.

Branch
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REL9_0_STABLE

Details
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http://git.postgresql.org/pg/commitdiff/9b3c35a9db418379fc760105df04ac30810f9c88

Modified Files
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src/backend/optimizer/util/clauses.c | 6 +++++-
1 files changed, 5 insertions(+), 1 deletions(-)