pgsql: C comment: add optimizer function reference

C comment: add optimizer function reference

Reported-by: James Coleman

Discussion: /messages/by-id/CAAaqYe9F6uoMhAr+8rMLwvGzaKaSknPA0Wi3Ehtv8pbSYmJq-Q@mail.gmail.com

Backpatch-through: master

Branch
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master

Details
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https://git.postgresql.org/pg/commitdiff/6d0c39a29309e5d7a6398e213190ae4f031061ab

Modified Files
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src/backend/optimizer/path/allpaths.c | 3 ++-
1 file changed, 2 insertions(+), 1 deletion(-)