pgsql: Fix location of output logs of pg_regress

Fix location of output logs of pg_regress

initdb.log and postmaster.log were moved to within the temporary instance
path by commit dcae5fa. This directory now gets removed at the end
of the run of pg_regress when there are no failures found, which makes
analysis of after-run issues difficult in some cases, and reduces the
output verbosity of the buildfarm after a run.

Fix by Michael Paquier

Backpatch to 9.5

Branch
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master

Details
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http://git.postgresql.org/pg/commitdiff/9faa6ae14f6098e4b55f0131f7ec2694a381fb87

Modified Files
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src/test/regress/pg_regress.c | 12 ++++++------
1 file changed, 6 insertions(+), 6 deletions(-)