pgsql: Fix oversight in pg_dump's handling of extension configuration t

Fix oversight in pg_dump's handling of extension configuration tables.

If an extension has not been selected to be dumped (perhaps because of
a --schema or --table switch), the contents of its configuration tables
surely should not get dumped either.  Per gripe from
Hubert Depesz Lubaczewski.

Branch
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REL9_1_STABLE

Details
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http://git.postgresql.org/pg/commitdiff/dd4e0a38781e0c48409f0c092b04b2ec75ed1a7e

Modified Files
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src/bin/pg_dump/pg_dump.c |    9 +++++++--
1 files changed, 7 insertions(+), 2 deletions(-)