pgsql: pg_upgrade: Ignore TOAST for partitioned tables

pg_upgrade: Ignore TOAST for partitioned tables

Since partitioned tables in pg12 do not have toast tables, trying to set
the toast OID confuses pg_upgrade.  Have pg_dump omit those values to
avoid the problem.

Per Andres Freund and buildfarm members crake and snapper
Discussion: https://postgr.es/m/20190306204104.yle5jfbnqkcwykni@alap3.anarazel.de

Branch
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master

Details
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https://git.postgresql.org/pg/commitdiff/203749a8a66096171f808dd8e870d08d8ad57e5e

Modified Files
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src/bin/pg_dump/pg_dump.c | 19 +++++++++++++++----
1 file changed, 15 insertions(+), 4 deletions(-)