pgsql: Fix pgbench's calculation of average latency, when -T is not use

Fix pgbench's calculation of average latency, when -T is not used.

If the test duration was given in # of transactions (-t or no option),
rather as a duration (-T), the latency average was always printed as 0.
It has been broken ever since the display of latency average was added,
in 9.4.

Fabien Coelho

Discussion: <alpine.DEB.2.20.1607131015370.7486@sto>

Branch
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REL9_6_STABLE

Details
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http://git.postgresql.org/pg/commitdiff/93834a20f67ee458c98067e253894457c5a958ad

Modified Files
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src/bin/pgbench/pgbench.c | 6 ++++--
1 file changed, 4 insertions(+), 2 deletions(-)