pgsql: libpq: Enforce ALPN in direct SSL connections

libpq: Enforce ALPN in direct SSL connections

ALPN is mandatory with direct SSL connections. That is documented, and
the server checks it, but libpq was missing the check.

Reported-by: Jacob Champion
Reviewed-by: Michael Paquier
Discussion: https://www.postgresql.org/message-id/CAOYmi+=sj+1uydS0NR4nYzw-LRWp3Q-s5speBug5UCLSPMbvGA@mail.gmail.com

Branch
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master

Details
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https://git.postgresql.org/pg/commitdiff/03a0e0d4bb78f23449802463ceea3c5bf8d4838a

Modified Files
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src/interfaces/libpq/fe-secure-openssl.c | 28 ++++++++++++++++++++++++++++
1 file changed, 28 insertions(+)