pgsql: libpq: remove unused field ssl_handshake_started from PGconn

libpq: remove unused field ssl_handshake_started from PGconn

The ssl_handshake_started field was added by d39a49c1e45 to allow
connection_failed() skip retrying with a different SSL negotiation
method, once the server had reported an error after the TLS handshake
had already started. That logic was dropped by fb5718f35ff, which
removed the ability to fall back from direct to negotiated SSL, and
with it the only consumer of the data in this field. Fix by removing
the field.

Author: Aleksander Alekseev <aleksander(at)tigerdata(dot)com>
Reviewed-by: Daniel Gustafsson <daniel(at)yesql(dot)se>
Discussion: https://postgr.es/m/CAJ7c6TPkHjVFERp1Fd-idMe=iRJnDX2Nzy_ZOkV=y4OLLgf89Q@mail.gmail.com

Branch
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master

Details
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https://git.postgresql.org/pg/commitdiff/bc86dc738e0e4c56a0635efd3d18b367b7e41f9b

Modified Files
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src/interfaces/libpq/fe-secure-openssl.c | 4 ----
src/interfaces/libpq/libpq-int.h | 1 -
2 files changed, 5 deletions(-)