pgsql: Reformat some node comments

Reformat some node comments

Reformat some comments in node field definitions to avoid long lines.
This makes room for per-field annotations. Similar to 835d476fd2.

Reviewed-by: Andrew Dunstan <andrew@dunslane.net>
Discussion: /messages/by-id/4b27fc50-8cd6-46f5-ab20-88dbaadca645@eisentraut.org

Branch
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master

Details
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https://git.postgresql.org/pg/commitdiff/d575051b9af99f9299dc33e627931ab612d8a147

Modified Files
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src/include/nodes/parsenodes.h | 86 ++++++++++++++++++++++++++++--------------
1 file changed, 57 insertions(+), 29 deletions(-)