pgsql: Remove leftover code in deconstruct_distribute_oj_quals().

Remove leftover code in deconstruct_distribute_oj_quals().

The initial "put back OJ relids" adjustment of ojscope was
incorrect and unnecessary; it seems to be a leftover from
when I (tgl) was trying to get this function to work at all.

Richard Guo

Discussion: https://postgr.es/m/CAMbWs4-L2C47ZGZPabBAi5oDZsKmsbvhYcGCy5o=gCjsaG_ZQA@mail.gmail.com

Branch
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master

Details
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https://git.postgresql.org/pg/commitdiff/2cbbffff05b853733ae19ca7047cfeb9a346a497

Modified Files
--------------
src/backend/optimizer/plan/initsplan.c |  7 -------
src/test/regress/expected/join.out     | 26 ++++++++++++++++++++++++++
src/test/regress/sql/join.sql          | 15 +++++++++++++++
3 files changed, 41 insertions(+), 7 deletions(-)