pgsql: Last-minute updates for release notes.

Last-minute updates for release notes.

Security: CVE-2019-10164

Branch
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REL_11_STABLE

Details
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https://git.postgresql.org/pg/commitdiff/a4e4418c3f68986607d7b588389e026108c79d71

Modified Files
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doc/src/sgml/release-11.sgml | 51 ++++++++++++++++++++++++++++++++------------
1 file changed, 37 insertions(+), 14 deletions(-)