pgsql: Undo overly enthusiastic de-const-ification.

Undo overly enthusiastic de-const-ification.

s/const//g wasn't exactly what I was suggesting here ... parameter
declarations of the form "const structtype *param" are good and useful,
so put those occurrences back.  Likewise, avoid casting away the const
in a "const void *" parameter.

Branch
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master

Details
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http://git.postgresql.org/pg/commitdiff/223be216afa13b708904ca1d72898f2ccf5cef40

Modified Files
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src/backend/storage/lmgr/predicate.c |   71 +++++++++++++++++-----------------
1 files changed, 35 insertions(+), 36 deletions(-)