Merge remote-tracking branch 'remotes/marcandre/tags/misc-pull-request' into staging

chardev & doc misc

# gpg: Signature made Tue 14 Sep 2021 13:59:10 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/marcandre/tags/misc-pull-request:
  chardev: add some comments about the class methods
  chardev: remove needless class method
  chardev: Propagate error from logfile opening
  meson.build: fix comment typo
  docs: add supported host CPU architectures section

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