Merge tag 'pull-nbd-2021-11-22' of https://repo.or.cz/qemu/ericb into staging

nbd patches for 2021-11-22

- Eric Blake: Avoid uninitialized memory on client hard disconnect
- Eric Blake: Take advantage of block layer 64-bit zero/trim

# gpg: Signature made Mon 22 Nov 2021 02:55:07 PM CET
# gpg:                using RSA key 71C2CC22B1C4602927D2F3AAA7A16B4A2527436A
# gpg: Good signature from "Eric Blake <eblake@redhat.com>" [full]
# gpg:                 aka "Eric Blake (Free Software Programmer) <ebb9@byu.net>" [full]
# gpg:                 aka "[jpeg image of size 6874]" [full]

* tag 'pull-nbd-2021-11-22' of https://repo.or.cz/qemu/ericb

:
  nbd/server: Simplify zero and trim
  nbd/server: Don't complain on certain client disconnects

Signed-off-by: Richard Henderson <richard.henderson@linaro.org>