pgsql: Support disallowing SSL renegotiation when using LibreSSL

Support disallowing SSL renegotiation when using LibreSSL

LibreSSL doesn't support the SSL_OP_NO_RENEGOTIATION macro which is
used by OpenSSL, instead it has invented a similar one for client-
side renegotiation: SSL_OP_NO_CLIENT_RENEGOTIATION. This has been
supported since LibreSSL 2.5.1 which by now can be considered well
below the minimum requirement.

Reviewed-by: Peter Eisentraut <peter@eisentraut.org>
Reviewed-by: Michael Paquier <michael@paquier.xyz>
Discussion: https://postgr.es/m/eac70d46-e61c-4d71-a1e1-78e2bfa19485@eisentraut.org

Branch
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master

Details
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https://git.postgresql.org/pg/commitdiff/44e27f0a6d07d194ee43e9e4095db75c0525112f

Modified Files
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src/backend/libpq/be-secure-openssl.c | 15 ++++++++++-----
1 file changed, 10 insertions(+), 5 deletions(-)