pgsql: More unconstify use

More unconstify use

Replace casts whose only purpose is to cast away const with the
unconstify() macro.

Discussion: https://www.postgresql.org/message-id/flat/53a28052-f9f3-1808-fed9-460fd43035ab%402ndquadrant.com

Branch
------
master

Details
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https://git.postgresql.org/pg/commitdiff/37d9916020286caec810f4de61fbd0de3568454d

Modified Files
--------------
contrib/btree_gist/btree_utils_num.c | 8 ++++----
contrib/pgcrypto/imath.c | 2 +-
contrib/pgcrypto/md5.c | 2 +-
contrib/pgcrypto/pgp-compress.c | 2 +-
src/backend/access/brin/brin_pageops.c | 8 ++++----
src/backend/access/transam/xact.c | 4 ++--
src/backend/executor/spi.c | 10 +++++-----
src/backend/libpq/auth.c | 10 +++++-----
src/backend/libpq/be-secure-openssl.c | 2 +-
src/backend/parser/parse_type.c | 2 +-
src/backend/replication/logical/message.c | 4 ++--
src/backend/tcop/postgres.c | 2 +-
src/backend/utils/adt/formatting.c | 2 +-
src/backend/utils/mb/mbutils.c | 20 ++++++++++----------
src/backend/utils/misc/guc.c | 2 +-
src/bin/pg_basebackup/pg_basebackup.c | 2 +-
src/bin/pg_basebackup/walmethods.c | 2 +-
src/bin/pg_dump/compress_io.c | 2 +-
src/bin/psql/prompt.c | 2 +-
src/fe_utils/print.c | 2 +-
src/interfaces/libpq/fe-lobj.c | 2 +-
src/interfaces/libpq/pqexpbuffer.c | 8 +++++---
src/pl/tcl/pltcl.c | 4 ++--
src/port/path.c | 6 +++---
src/timezone/localtime.c | 2 +-
25 files changed, 57 insertions(+), 55 deletions(-)