pgsql: Adjust pgbench option for debug mode.

Adjust pgbench option for debug mode.

Many other utilities use -d to specify the database to use, but
pgbench uses it to enable debug mode. This is causing some users
to accidentally enable it. This commit changes -d to accept the
database name and introduces --dbname. Debug mode can still be
enabled with --debug. This is a backward-incompatible change, but
it has been judged to be worth the trade-off, i.e., some scripts
that use pgbench will need to be updated.

Author: Greg Sabino Mullane
Reviewed-by: Tomas Vondra, Euler Taveira, Alvaro Herrera, David Christensen
Discussion: https://postgr.es/m/CAKAnmmLjAzwVtb%3DVEaeuCtnmOLpzkJ1uJ_XiQ362YdD9B72HSg%40mail.gmail.com

Branch
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master

Details
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https://git.postgresql.org/pg/commitdiff/3ff01b2b6e7e8627b191a2c8c2690c8ea2f0820d

Modified Files
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doc/src/sgml/ref/pgbench.sgml | 4 ++--
src/bin/pgbench/pgbench.c | 32 +++++++++++++++++-----------
src/bin/pgbench/t/001_pgbench_with_server.pl | 2 +-
src/bin/pgbench/t/002_pgbench_no_server.pl | 2 +-
4 files changed, 24 insertions(+), 16 deletions(-)