Merge remote-tracking branch 'remotes/mdroth/tags/qga-pull-2020-03-24-tag0' into...

qemu-ga patch queue for hard-freeze

* fix undefined C behavior with guest-file-* interfaces
* fix w32 installer issues
* fix crash for large file reads via guest-file-read on windows
* add missing man page documentation for virtio-vsock

# gpg: Signature made Tue 24 Mar 2020 16:45:24 GMT
# gpg:                using RSA key CEACC9E15534EBABB82D3FA03353C9CEF108B584
# gpg:                issuer "mdroth@linux.vnet.ibm.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-2020-03-24-tag0:
  qemu-ga: document vsock-listen in the man page
  qga: Fix undefined C behavior
  qga-win: prevent crash when executing guest-file-read with large count
  qga-win: Handle VSS_E_PROVIDER_ALREADY_REGISTERED error
  qga: Installer: Wait for installation to finish

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