pgsql: pgbench: Correct log level of message output when socket wait me

pgbench: Correct log level of message output when socket wait method fails.

The failure of socket wait method like "select()" doesn't terminate pgbench.
So the log level of error message when that failure happens should be ERROR.
But previously FATAL was used in that case.

Back-patch to v13 where pgbench started using common logging API.

Author: Yugo Nagata, Fabien COELHO
Reviewed-by: Kyotaro Horiguchi, Fujii Masao
Discussion: https://postgr.es/m/20210617005934.8bd37bf72efd5f1b38e6f482@sraoss.co.jp

Branch
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master

Details
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https://git.postgresql.org/pg/commitdiff/d33674708948e10806480ee628b072a2ef8ecba1

Modified Files
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src/bin/pgbench/pgbench.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)