Link to pgport earlier

I would like to apply this to CVS HEAD and 8.0.X so PG client
applications link to the libpgport non-shared library before linking to
libpq so it doesn't pull libpgport symbols from libpq.

This should make PG client apps more immune to libpq/pgport changes in
each version.

-- 
  Bruce Momjian                        |  http://candle.pha.pa.us
  pgman@candle.pha.pa.us               |  (610) 359-1001
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