Merge remote-tracking branch 'remotes/qmp-unstable/queue/qmp' into staging

Merge remote-tracking branch 'remotes/qmp-unstable/queue/qmp' into staging

* remotes/qmp-unstable/queue/qmp: (43 commits)
  monitor: protect event emission
  monitor: protect outbuf and mux_out with mutex
  qemu-char: make writes thread-safe
  qemu-char: move pty_chr_update_read_handler around
  qemu-char: do not call chr_write directly
  qemu-char: introduce qemu_chr_alloc
  qapi event: clean up
  qapi event: convert QUORUM events
  qapi event: convert GUEST_PANICKED
  qapi event: convert BALLOON_CHANGE
  qmp: convert ACPI_DEVICE_OST event
  qapi event: convert SPICE events
  qapi event: convert VNC events
  qapi event: convert NIC_RX_FILTER_CHANGED
  qapi event: convert other BLOCK_JOB events
  qapi event: convert BLOCK_IMAGE_CORRUPTED
  qapi event: convert BLOCK_IO_ERROR and BLOCK_JOB_ERROR
  qapi event: convert DEVICE_TRAY_MOVED
  qapi event: convert DEVICE_DELETED
  qapi event: convert WATCHDOG
  ...

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