pgsql: Delay creation of SSL_CTX structure to allow cleanup

Delay creation of SSL_CTX structure to allow cleanup

Avoid initializing the OpenSSL SSL_CTX structure for a new host
until it has been checked for errors. The cleanup can only see
hosts which were successfully added so the previous coding would
leak the SSL_CTX on failed reloads.

Author: Zsolt Parragi <zsolt(dot)parragi(at)percona(dot)com>
Reviewed-by: Daniel Gustafsson <daniel(at)yesql(dot)se>
Reviewed-by: Rui Zhao <zhaorui126(at)gmail(dot)com>
Discussion: https://postgr.es/m/A1745424-7110-41E9-B98C-3CED1A034A8F@yesql.se
Backpatch-through: 19

Branch
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master

Details
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https://git.postgresql.org/pg/commitdiff/b0faa1d2142a088963f8e0d0cf0ce9e5fe268223

Modified Files
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src/backend/libpq/be-secure-openssl.c | 11 ++++++++---
1 file changed, 8 insertions(+), 3 deletions(-)