pgsql: Reformat some more node comments

Reformat some more node comments

Reformat some more comments in node field definitions to avoid long
lines. Similar to 835d476fd21bcfb60b055941dee8c3d9559af14c, based on
additional per-field annotations that will be required.

Discussion: /messages/by-id/c5906b07-220a-a3d4-8ff3-8ee593009424@enterprisedb.com

Branch
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master

Details
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https://git.postgresql.org/pg/commitdiff/3140f089855c03035ee354aa115618068f8d0206

Modified Files
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src/include/nodes/pathnodes.h | 260 +++++++++++++++++++++++++++---------------
src/include/utils/rel.h | 26 +++--
2 files changed, 189 insertions(+), 97 deletions(-)