pgsql: Remove extract_autovac_opts().

Remove extract_autovac_opts().

extract_autovac_opts() returns a palloc'd copy of just the
AutoVacOpts portion of a relation's reloptions, but upcoming work
needs the other StdRdOptions fields, too. Remove it in favor of
calling extractRelOptions() directly. av_relation now caches the
main table's whole StdRdOptions.

Reviewed-by: Michael Paquier <michael(at)paquier(dot)xyz>
Reviewed-by: Sami Imseih <samimseih(at)gmail(dot)com>
Tested-by: Greg Burd <greg(at)burd(dot)me>
Tested-by: solai v <solai(dot)cdac(at)gmail(dot)com>
Discussion: https://postgr.es/m/aFRxC1W_kZU9OjJ9%40nathan

Branch
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master

Details
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https://git.postgresql.org/pg/commitdiff/0499c6ccf5ce510ad8c57211ee8c9414e92c71b7

Modified Files
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src/backend/postmaster/autovacuum.c | 85 +++++++++++++------------------------
1 file changed, 29 insertions(+), 56 deletions(-)