pgsql: Remove partColsUpdated.

Remove partColsUpdated.

This information appears to have been unused since commit
c5b7ba4e67. We could not find any references in third-party code,
either.

Reviewed-by: Chao Li <li(dot)evan(dot)chao(at)gmail(dot)com>
Reviewed-by: Tom Lane <tgl(at)sss(dot)pgh(dot)pa(dot)us>
Reviewed-by: Michael Paquier <michael(at)paquier(dot)xyz>
Discussion: https://postgr.es/m/aO_CyFRpbVMtgJWM%40nathan

Branch
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master

Details
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https://git.postgresql.org/pg/commitdiff/812221b204276b884d2b14ef56aabd9e1946be81

Modified Files
--------------
src/backend/optimizer/plan/createplan.c | 4 ----
src/backend/optimizer/plan/planner.c | 2 --
src/backend/optimizer/util/inherit.c | 10 ----------
src/backend/optimizer/util/pathnode.c | 4 ----
src/include/nodes/pathnodes.h | 4 ----
src/include/nodes/plannodes.h | 2 --
src/include/optimizer/pathnode.h | 1 -
7 files changed, 27 deletions(-)