pgsql: Remove outdated comment about relation level autovacuum freeze l

Remove outdated comment about relation level autovacuum freeze limits.

The documentation for the autovacuum_multixact_freeze_max_age and
autovacuum_freeze_max_age relation level parameters contained:
"Note that while you can set autovacuum_multixact_freeze_max_age very
small, or even zero, this is usually unwise since it will force frequent
vacuuming."
which hasn't been true since these options were made relation options,
instead of residing in the pg_autovacuum table (834a6da4f7).

Remove the outdated sentence. Even the lowered limits from 2596d70 are
high enough that this doesn't warrant calling out the risk in the CREATE
TABLE docs.

Per discussion with Tom Lane and Alvaro Herrera

Discussion: 26377(dot)1443105453(at)sss(dot)pgh(dot)pa(dot)us
Backpatch: 9.0- (in parts)

Branch
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REL9_0_STABLE

Details
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http://git.postgresql.org/pg/commitdiff/c415a7c8982b37818b9db50e2cb3f349f76550a7

Modified Files
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doc/src/sgml/ref/create_table.sgml | 4 +---
1 file changed, 1 insertion(+), 3 deletions(-)