Обсуждение: pgsql: Update some obsolete comments.

Update some obsolete comments.

Fix a few stray references to expression eval functions that don't
exist anymore or don't take the same input representation they used to.

Branch
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master

Details
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http://git.postgresql.org/pg/commitdiff/244dd95ce9d9831f8498f5746860325f7adcecbf

Modified Files
--------------
src/backend/optimizer/util/clauses.c | 4 ++--
src/backend/utils/cache/relcache.c   | 2 +-
src/pl/plpgsql/src/pl_exec.c         | 2 +-
3 files changed, 4 insertions(+), 4 deletions(-)