pgsql: Prevent passing gmake's environment variables down through pg_re

Prevent passing gmake's environment variables down through pg_regress.

When we do "make install" to create a temp installation, we don't want
that instance of make to try to communicate with any instance of make
that might be calling us.  This is known to cause problems if the
upper make has a -jN flag, and in principle could cause problems even
without that.  Unset the relevant environment variables to prevent such
issues.

Andres Freund

Branch
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master

Details
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http://git.postgresql.org/pg/commitdiff/c35fea102628fedf9e62c6a440073257676a873b

Modified Files
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src/test/regress/pg_regress.c |   13 +++++++++++++
1 files changed, 13 insertions(+), 0 deletions(-)