pgsql: Document ANALYZE storage parameters for partitioned tables

Document ANALYZE storage parameters for partitioned tables

Commit 0827e8af70f4 added parameters for autovacuum to support
partitioned tables, but didn't add any docs.  Add them.

Discussion: https://postgr.es/m/20210408213051.GL6592@telsasoft.com

Branch
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master

Details
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https://git.postgresql.org/pg/commitdiff/41badeaba8beee7648ebe7923a41c04f1f3cb302

Modified Files
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doc/src/sgml/ref/create_table.sgml | 8 ++++++--
1 file changed, 6 insertions(+), 2 deletions(-)