Merge remote-tracking branch 'remotes/mdroth/tags/qga-pull-2020-10-27-v3-tag' into staging

qemu-ga patch queue for soft-freeze

* add guest-get-disks for w32/linux
* add guest-{add,remove,get}-authorized-keys
* fix API violations and schema documentation inconsistencies with
  recently-added guest-get-devices

v3:
- fix checkpatch errors regarding disallowed usages of g_assert*
  macros and other warnings

v2:
- fix BSD build error due to missing stub for guest_get_disks
- fix clang build error on linux due to unused variable
- disable qga-ssh-test for now due to a memory leak within GLib when
  G_TEST_OPTION_ISOLATE_DIRS is passed to g_test_init() since it
  break Gitlab CI build-oss-fuzz test
- rebased and re-tested on master

# gpg: Signature made Tue 03 Nov 2020 02:30:50 GMT
# gpg:                using RSA key CEACC9E15534EBABB82D3FA03353C9CEF108B584
# gpg:                issuer "michael.roth@amd.com"
# gpg: Good signature from "Michael Roth <flukshun@gmail.com>" [full]
# gpg:                 aka "Michael Roth <mdroth@utexas.edu>" [full]
# gpg:                 aka "Michael Roth <mdroth@linux.vnet.ibm.com>" [full]
# Primary key fingerprint: CEAC C9E1 5534 EBAB B82D  3FA0 3353 C9CE F108 B584

* remotes/mdroth/tags/qga-pull-2020-10-27-v3-tag:
  qga: add ssh-get-authorized-keys
  meson: minor simplification
  qga: add *reset argument to ssh-add-authorized-keys
  qga: add ssh-{add,remove}-authorized-keys
  glib-compat: add g_unix_get_passwd_entry_qemu()
  qga: add implementation of guest-get-disks for Windows
  qga: add implementation of guest-get-disks for Linux
  qga: add command guest-get-disks
  qga: Flatten simple union GuestDeviceId
  qga-win: Fix guest-get-devices error API violations
  qga: Use common time encoding for guest-get-devices 'driver-date'
  qga: Rename guest-get-devices return member 'address' to 'id'

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