pgsql: Remove various unnecessary (char *) casts

Remove various unnecessary (char *) casts

Remove a number of (char *) casts that are unnecessary. Or in some
cases, rewrite the code to make the purpose of the cast clearer.

Reviewed-by: Dagfinn Ilmari Mannsåker <ilmari@ilmari.org>
Discussion: /messages/by-id/fd1fcedb-3492-4fc8-9e3e-74b97f2db6c7@eisentraut.org

Branch
------
master

Details
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https://git.postgresql.org/pg/commitdiff/3e4d868615408370fe6c2977c32f45a47c372b00

Modified Files
--------------
contrib/ltree/ltxtquery_io.c | 2 +-
contrib/pg_trgm/trgm_gist.c | 10 +++++-----
contrib/postgres_fdw/postgres_fdw.c | 8 ++++----
src/backend/access/transam/xlog.c | 4 ++--
src/backend/libpq/auth.c | 8 +++++---
src/backend/nodes/copyfuncs.c | 2 +-
src/backend/nodes/makefuncs.c | 2 +-
src/backend/storage/page/bufpage.c | 2 +-
src/backend/utils/cache/relmapper.c | 4 ++--
src/backend/utils/error/jsonlog.c | 2 +-
src/bin/pg_basebackup/pg_receivewal.c | 2 +-
src/bin/pg_dump/compress_gzip.c | 2 +-
src/bin/pg_rewind/pg_rewind.c | 2 +-
src/bin/psql/describe.c | 2 +-
src/common/controldata_utils.c | 4 ++--
src/interfaces/ecpg/ecpglib/descriptor.c | 4 ++--
src/interfaces/ecpg/ecpglib/execute.c | 2 +-
src/interfaces/ecpg/pgtypeslib/numeric.c | 4 ++--
18 files changed, 34 insertions(+), 32 deletions(-)