pgsql: Specify the port in dblink and postgres_fdw tests.

Specify the port in dblink and postgres_fdw tests.

That allows to run those tests against a postmaster listening on a
nonstandard port without requiring to export PGPORT in postmaster's
environment.

This still doesn't support connecting to a nondefault host without
configuring it in postmaster's environment. That's harder and less
frequently used though. So this is a useful step.

Branch
------
master

Details
-------
http://git.postgresql.org/pg/commitdiff/57ca1d4f0175f60e9cfb0f997c864173d9c72607

Modified Files
--------------
contrib/dblink/expected/dblink.out             |    6 ++++--
contrib/dblink/sql/dblink.sql                  |    6 ++++--
contrib/postgres_fdw/expected/postgres_fdw.out |    4 +++-
contrib/postgres_fdw/sql/postgres_fdw.sql      |    4 +++-
4 files changed, 14 insertions(+), 6 deletions(-)