pgsql: Small tidyup for commit d41a178b.

Small tidyup for commit d41a178b.

A comment was left behind claiming that we needed to use malloc() rather
than palloc() because the corresponding free would run in another
thread, but that's not true anymore. Remove that comment. And, with
the reason being gone, we might as well actually use palloc().

Back-patch to supported releases, like d41a178b.

Discussion: https://postgr.es/m/CA%2BhUKG%2BpdM9v3Jv4tc2BFx2jh_daY3uzUyAGBhtDkotEQDNPYw%40mail.gmail.com

Branch
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REL_14_STABLE

Details
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https://git.postgresql.org/pg/commitdiff/00fc4b3a31010033e8b1a964c90a7a30b8d6a7d7

Modified Files
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src/backend/postmaster/postmaster.c | 11 ++++-------
1 file changed, 4 insertions(+), 7 deletions(-)