Add the RHEL 211.19.1..211.20.1 backports (1245-1287) from centos-stream-10 and
upstream, on top of 211.18.1, plus the dpll RHEL kABI adaptation (1287). RHEL now
ships the smb cifs.spnego fix too; the existing ahead-fix 1105 is byte-identical,
so RHEL's redundant copy is omitted. Bump to 211.20.1.
