pgsql: Improve log messages related to pg_hba.conf not matching a conne

Improve log messages related to pg_hba.conf not matching a connection.

Include details on whether GSS encryption has been activated;
since we added "hostgssenc" type HBA entries, that's relevant info.

Kyotaro Horiguchi and Tom Lane.  Back-patch to v12 where
GSS encryption was introduced.

Discussion: https://postgr.es/m/e5b0b6ed05764324a2f3fe7acfc766d5@smhi.se

Branch
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master

Details
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https://git.postgresql.org/pg/commitdiff/3995c424984e991b1069a2869af972dc07574c0b

Modified Files
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src/backend/libpq/auth.c | 72 +++++++++++++++++++-----------------------------
1 file changed, 28 insertions(+), 44 deletions(-)