pgsql: Remove unnecessary casts

Remove unnecessary casts

Some code carefully cast all data buffer arguments for BufFileWrite()
and BufFileRead() to void *, even though the arguments are already
void * (and AFAICT were never anything else). Remove this unnecessary
clutter.

Discussion: https://www.postgresql.org/message-id/flat/11dda853-bb5b-59ba-a746-e168b1ce4bdb%40enterprisedb.com

Branch
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master

Details
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https://git.postgresql.org/pg/commitdiff/07c29ca7fe30839a75d15b43c13b290a59a60ddf

Modified Files
--------------
src/backend/executor/nodeHashjoin.c | 8 ++++----
src/backend/utils/sort/tuplestore.c | 12 ++++++------
2 files changed, 10 insertions(+), 10 deletions(-)