pgsql: Remove outdated reference to RAID spindles.

Remove outdated reference to RAID spindles.

Commit b09ff536 left behind some outdated advice in the long_desc field
of the GUC "effective_io_concurrency".  Remove it.

Back-patch to 13.

Reported-by: Andrew Gierth <[hidden email]>
Reviewed-by: Julien Rouhaud <[hidden email]>
Discussion: https://postgr.es/m/CA%2BhUKGJyyWqFBxL9gEj-qtjBThGjhAOBE8GBnF8MUJOJ3vrfag%40mail.gmail.com

Branch
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REL_13_STABLE

Details
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https://git.postgresql.org/pg/commitdiff/5190ce845c59727ed7177dadd62626d6450a55bd

Modified Files
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src/backend/utils/misc/guc.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)