pgsql: Support SSL_R_VERSION_TOO_LOW when using LibreSSL

Support SSL_R_VERSION_TOO_LOW when using LibreSSL

The SSL_R_VERSION_TOO_LOW error reason is supported in LibreSSL since
LibreSSL 3.6.3, shipped in OpenBSD 7.2. SSL_R_VERSION_TOO_HIGH is on
the other hand not supported in any version of LibreSSL. Previously
we only checked for SSL_R_VERSION_TOO_HIGH and then applied both under
that guard since OpenSSL has only ever supported both at the same time.
This breaks the check into one per reason to allow SSL_R_VERSION_TOO_LOW
to work when using LibreSSL.

Reviewed-by: Peter Eisentraut <peter(at)eisentraut(dot)org>
Reviewed-by: Michael Paquier <michael(at)paquier(dot)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/d80f2ce294653ce633984445c971dfb534578464

Modified Files
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src/backend/libpq/be-secure-openssl.c | 2 ++
1 file changed, 2 insertions(+)