pgsql: Pull in tableoid for inheiritance with rowMarks

Pull in tableoid for inheiritance with rowMarks

As noted by Etsuro Fujita [1] and Dean Rasheed[2],
cb1ca4d800621dcae67ca6c799006de99fa4f0a5 changed ExecBuildAuxRowMark()
to always look for the tableoid in the target list, but didn't also
change preprocess_targetlist() to always include the tableoid.  This
resulted in errors with soon-to-be-added RLS with inheritance tests,
and errors when using inheritance with foreign tables.

Authors: Etsuro Fujita and Dean Rasheed (independently)

Minor word-smithing on the comments by me.

[1] 552CF0B6.8010006@lab.ntt.co.jp
[2] CAEZATCVmFUfUOwwhnBTcgi6AquyjQ0-1fyKd0T3xBWJvn+xsFA@mail.gmail.com

Branch
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master

Details
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http://git.postgresql.org/pg/commitdiff/4ccc5bd28e7f0c0d1b221683398ae178515b9f76

Modified Files
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contrib/postgres_fdw/expected/postgres_fdw.out |   52 ++++++++++++------------
src/backend/optimizer/prep/preptlist.c         |   34 ++++++++--------
2 files changed, 43 insertions(+), 43 deletions(-)