pgsql: Re-Align *_freeze_max_age reloption limits with corresponding GU

Re-Align *_freeze_max_age reloption limits with corresponding GUC limits.

In 020235a5754 I lowered the autovacuum_*freeze_max_age minimums to
allow for easier testing of wraparounds. I did not touch the
corresponding per-table limits. While those don't matter for the purpose
of wraparound, it seems more consistent to lower them as well.

It's noteworthy that the previous reloption lower limit for
autovacuum_multixact_freeze_max_age was too high by one magnitude, even
before 020235a5754.

Discussion: 26377(dot)1443105453(at)sss(dot)pgh(dot)pa(dot)us
Backpatch: back to 9.0 (in parts), like the prior patch

Branch
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REL9_4_STABLE

Details
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http://git.postgresql.org/pg/commitdiff/13ac4c035de96eb66c87bfba7faf4c5890293c36

Modified Files
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src/backend/access/common/reloptions.c | 4 ++--
1 file changed, 2 insertions(+), 2 deletions(-)