pgsql: Remove useless flag PVC_INCLUDE_CONVERTROWTYPES.

Remove useless flag PVC_INCLUDE_CONVERTROWTYPES.

This was introduced in the SJE patch (fc069a3a6), but it doesn't
do anything because pull_var_clause() never tests it. Apparently
it snuck in from somebody's private fork. Remove it again, but
only in HEAD -- seems best to let it be in v18.

Author: Alexander Pyhalov <a(dot)pyhalov(at)postgrespro(dot)ru>
Reviewed-by: Tom Lane <tgl(at)sss(dot)pgh(dot)pa(dot)us>
Discussion: https://postgr.es/m/70008c19d22e3dd1565ca57f8436c0ba@postgrespro.ru

Branch
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master

Details
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https://git.postgresql.org/pg/commitdiff/cec5fe0d1e192b3b0005063011f113ac99f6908c

Modified Files
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src/backend/optimizer/path/equivclass.c | 3 +--
src/include/optimizer/optimizer.h | 2 --
2 files changed, 1 insertion(+), 4 deletions(-)