pgsql: Fix some assorted compiler warnings on Windows.

Fix some assorted compiler warnings on Windows.

Don't overflow the result type of constant expressions. Don't negate
unsigned types. Define HAVE_STDBOOL_H for Visual C++ 2013 and later.

Thomas Munro
Reviewed-By: Michael Paquier and Tom Lane

Discussion: /messages/by-id/CAEepm=3=TDYEXUEcHpEx+Twc31wo7PA0oBAiNt6sWmq93MW02A@mail.gmail.com

Branch
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master

Details
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https://git.postgresql.org/pg/commitdiff/b2328bf62b6465236e318d31a011ced5dccfd580

Modified Files
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src/backend/replication/basebackup.c | 2 +-
src/bin/pgbench/pgbench.c | 3 ++-
src/include/pg_config.h.win32 | 4 +++-
3 files changed, 6 insertions(+), 3 deletions(-)