pgsql: Improve pg_dump's query for retrieving BLOB comments to be more

Log Message:
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Improve pg_dump's query for retrieving BLOB comments to be more efficient
when there are many blobs and not so many comments. Tamas Vincze

Tags:
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REL8_3_STABLE

Modified Files:
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pgsql/src/bin/pg_dump:
pg_dump.c (r1.482.2.1 -> r1.482.2.2)
(http://anoncvs.postgresql.org/cvsweb.cgi/pgsql/src/bin/pg_dump/pg_dump.c?r1=1.482.2.1&r2=1.482.2.2)