pgsql: Fix two issues with custom_query_jumble in gen_node_support.pl

Fix two issues with custom_query_jumble in gen_node_support.pl

A node field marked with custom_query_jumble and query_jumble_ignore
would generate some code of a custom routine. The script is changed so
as custom_query_jumble behaves like the other options in this case,
query_jumble_ignore taking priority, with no code generated.

A comment related to the code generated for node types was misplaced.

Thinkos introduced in 5ac462e2b7ac.

Reported-by: Tom Lane <tgl(at)sss(dot)pgh(dot)pa(dot)us>
Discussion: https://postgr.es/m/1324036.1742945060@sss.pgh.pa.us

Branch
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master

Details
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https://git.postgresql.org/pg/commitdiff/27ee6ede6bc9ee287f321d396c5c777083d40ecd

Modified Files
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src/backend/nodes/gen_node_support.pl | 6 +++---
1 file changed, 3 insertions(+), 3 deletions(-)