pgsql: Remove duplicate setting of SSL_OP_SINGLE_DH_USE option.

Remove duplicate setting of SSL_OP_SINGLE_DH_USE option.

Commit c0a15e07c moved the setting of OpenSSL's SSL_OP_SINGLE_DH_USE option
into a new subroutine initialize_dh(), but forgot to remove it from where
it was. SSL_CTX_set_options() is a trivial function, amounting indeed to
just "ctx->options |= op", hence there's no reason to contort the code or
break separation of concerns to avoid calling it twice. So separating the
DH setup from disabling of old protocol versions is a good change, but we
need to finish the job.

Noted while poking into the question of SSL session tickets.

Branch
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master

Details
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https://git.postgresql.org/pg/commitdiff/f352f91cbf2f662c4f043d3650010b02da0cde1c

Modified Files
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src/backend/libpq/be-secure-openssl.c | 4 +---
1 file changed, 1 insertion(+), 3 deletions(-)