pgsql: Fix minor thinko in logic to set dump order when dumping from a

Log Message:
-----------
Fix minor thinko in logic to set dump order when dumping from a pre-7.3
database: aggregates should be dumped in the same pass as operators,
not in the same pass as functions.

Modified Files:
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pgsql/src/bin/pg_dump:
pg_dump_sort.c (r1.8 -> r1.9)
(http://developer.postgresql.org/cvsweb.cgi/pgsql/src/bin/pg_dump/pg_dump_sort.c.diff?r1=1.8&r2=1.9)