Обсуждение: pgsql: Update comments on CustomPath struct.

Update comments on CustomPath struct.

Commit e7cb7ee14 allowed custom scan providers to create CustomPath
paths for join relations as well, but missed updating the comments.

Back-patch to all supported branches.

Discussion: https://postgr.es/m/CAPmGK15ODkN%2B%3DhkBCufj1HBW0x5OTb65Xuy7ryXchMdiCMpx_g%40mail.gmail.com

Branch
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REL_12_STABLE

Details
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https://git.postgresql.org/pg/commitdiff/329f3a4bbab1b3f5e43076187601f9799befa3b2

Modified Files
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src/include/nodes/pathnodes.h | 13 ++++++++-----
1 file changed, 8 insertions(+), 5 deletions(-)