Merge remote-tracking branch 'remotes/elmarco/tags/chardev-pull-request' into staging

# gpg: Signature made Mon 13 Jul 2020 09:23:19 BST
# gpg:                using RSA key 87A9BD933F87C606D276F62DDAE8E10975969CE5
# gpg:                issuer "marcandre.lureau@redhat.com"
# gpg: Good signature from "Marc-André Lureau <marcandre.lureau@redhat.com>" [full]
# gpg:                 aka "Marc-André Lureau <marcandre.lureau@gmail.com>" [full]
# Primary key fingerprint: 87A9 BD93 3F87 C606 D276  F62D DAE8 E109 7596 9CE5

* remotes/elmarco/tags/chardev-pull-request:
  chardev: Extract system emulation specific code
  chardev: Reduce "char-mux.h" scope, rename it "chardev-internal.h"
  chardev: Restrict msmouse / wctablet / testdev to system emulation
  tests/test-char: Remove unused "chardev/char-mux.h" include
  monitor/misc: Remove unused "chardev/char-mux.h" include
  char: fix use-after-free with dup chardev & reconnect
  chardev: don't abort on attempt to add duplicated chardev
  char-socket: initialize reconnect timer only when the timer doesn't start

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