pgsql: Minor fixes for search path cache code.

Minor fixes for search path cache code.

Avoid leaving a dangling pointer in the unlikely event that
nsphash_create fails. Improve comments, and fix formatting by
adding typedefs.list entries.

Discussion: /messages/by-id/3972900.1704145107@sss.pgh.pa.us

Branch
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master

Details
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https://git.postgresql.org/pg/commitdiff/ae6bc39317f59dff5eb549e77d3f7e330e9ba075

Modified Files
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src/backend/catalog/namespace.c | 44 +++++++++++++++++++---------------------
src/tools/pgindent/typedefs.list | 3 +++
2 files changed, 24 insertions(+), 23 deletions(-)