pgsql: Fix memory leak in libpq when using sslmode=verify-full

Fix memory leak in libpq when using sslmode=verify-full

Checking if Subject Alternative Names (SANs) from a certificate match
with the hostname connected to leaked memory after each lookup done.

This is broken since acd08d7 that added support for SANs in SSL
certificates, so backpatch down to 9.5.

Author: Roman Peshkurov
Reviewed-by: Hamid Akhtar, Michael Paquier, David Steele
Discussion: https://postgr.es/m/CALLDf-pZ-E3mjxd5=bnHsDu9zHEOnpgPgdnO84E2RuwMCjjyPw@mail.gmail.com
Backpatch-through: 9.5

Branch
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REL_12_STABLE

Details
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https://git.postgresql.org/pg/commitdiff/e1c08722ae0219634147f8a05876a5ef0df9be93

Modified Files
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src/interfaces/libpq/fe-secure-openssl.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)