pgsql: Fix typo in freeze_table_age implementation

Fix typo in freeze_table_age implementation

The original code used freeze_min_age instead of freeze_table_age.  The
main consequence of this mistake is that lowering freeze_min_age would
cause full-table scans to occur much more frequently, which causes
serious issues because the number of writes required is much larger.
That feature (freeze_min_age) is supposed to affect only how soon tuples
are frozen; some pages should still be skipped due to the visibility
map.

Backpatch to 8.4, where the freeze_table_age feature was introduced.

Report and patch from Andres Freund

Branch
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REL9_0_STABLE

Details
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http://git.postgresql.org/pg/commitdiff/275a86bed8a09d372eb8e02966a847f0321aaa32

Modified Files
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src/backend/commands/vacuum.c |    2 +-
1 files changed, 1 insertions(+), 1 deletions(-)