pgsql: Update some comments that should've covered MERGE - Mailing list pgsql-committers

Update some comments that should've covered MERGE

Oversight in 7103ebb7aae8.  Backpatch to 15.

Author: Richard Guo <guofenglinux@gmail.com>
Discussion: https://postgr.es/m/CAMbWs48gnDjZXq3-b56dVpQCNUJ5hD9kdtWN4QFwKCEapspNsA@mail.gmail.com

Branch
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REL_15_STABLE

Details
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https://git.postgresql.org/pg/commitdiff/fb2a83b2b750a32ddfd107a75a3bc173f4f0a81f

Modified Files
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src/backend/optimizer/path/indxpath.c   | 13 +++++++------
src/backend/optimizer/plan/planmain.c   |  2 +-
src/backend/optimizer/plan/planner.c    |  4 ++--
src/backend/optimizer/util/appendinfo.c |  6 +++---
src/backend/optimizer/util/inherit.c    |  2 +-
src/backend/optimizer/util/pathnode.c   |  3 ++-
src/backend/optimizer/util/relnode.c    |  2 +-
src/backend/parser/parse_clause.c       |  6 ++++--
src/backend/parser/parse_expr.c         |  4 ++--
src/backend/parser/parse_merge.c        |  6 +++++-
src/include/nodes/parsenodes.h          |  4 ++--
src/include/nodes/pathnodes.h           | 16 ++++++++--------
src/include/nodes/plannodes.h           |  4 ++--
src/include/nodes/primnodes.h           |  4 ++--
14 files changed, 42 insertions(+), 34 deletions(-)