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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master

Details
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https://git.postgresql.org/pg/commitdiff/6a9229da65c9553a1268764d46fb28043b83bfd6

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