pgsql: Fix ps display for IO workers.

Fix ps display for IO workers.

This code must have missed a memo about the backend type description
being supplied automatically these days, and was duplicating that
information.

Before: "io worker io worker: N"
After:  "io worker N"

Branch
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master

Details
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https://git.postgresql.org/pg/commitdiff/e51ca405ed823b28358f216642b5a80f1f886f5d

Modified Files
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src/backend/storage/aio/method_worker.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)