Merge tag 'pull-9p-20221223' of https://github.com/cschoenebeck/qemu into staging

9pfs: Windows host prep, cleanup

* Next preparatory patches for upcoming Windows host support.

* Cleanup patches.

# gpg: Signature made Fri 23 Dec 2022 11:04:26 GMT
# gpg:                using RSA key 96D8D110CF7AF8084F88590134C2B58765A47395
# gpg:                issuer "qemu_oss@crudebyte.com"
# gpg: Good signature from "Christian Schoenebeck <qemu_oss@crudebyte.com>" [unknown]
# gpg: WARNING: This key is not certified with a trusted signature!
# gpg:          There is no indication that the signature belongs to the owner.
# Primary key fingerprint: ECAB 1A45 4014 1413 BA38  4926 30DB 47C3 A012 D5F4
#      Subkey fingerprint: 96D8 D110 CF7A F808 4F88  5901 34C2 B587 65A4 7395

* tag 'pull-9p-20221223' of https://github.com/cschoenebeck/qemu:
  hw/9pfs: Replace the direct call to xxxat() APIs with a wrapper
  hw/9pfs: Drop unnecessary *xattr wrapper API declarations
  qemu/xattr.h: Exclude <sys/xattr.h> for Windows
  MAINTAINERS: Add 9p test client to section "virtio-9p"
  9pfs: Fix some return statements in the synth backend

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>