pgsql: Last-minute updates for release notes.

Last-minute updates for release notes.

Security: CVE-2022-1552

Branch
------
REL_11_STABLE

Details
-------
https://git.postgresql.org/pg/commitdiff/b5576e1b701c8d690ed1ea8d3c17d5df49de3d7c

Modified Files
--------------
doc/src/sgml/release-11.sgml | 81 ++++++++++++++++++++++++++++++++------------
1 file changed, 59 insertions(+), 22 deletions(-)