Merge remote-tracking branch 'remotes/armbru/tags/pull-qapi-2020-09-29' into staging

QAPI patches patches for 2020-09-29

# gpg: Signature made Tue 29 Sep 2020 20:54:51 BST
# gpg:                using RSA key 354BC8B3D7EB2A6B68674E5F3870B400EB918653
# gpg:                issuer "armbru@redhat.com"
# gpg: Good signature from "Markus Armbruster <armbru@redhat.com>" [full]
# gpg:                 aka "Markus Armbruster <armbru@pond.sub.org>" [full]
# Primary key fingerprint: 354B C8B3 D7EB 2A6B 6867  4E5F 3870 B400 EB91 8653

* remotes/armbru/tags/pull-qapi-2020-09-29: (29 commits)
  Remove texinfo dependency from docker and CI configs
  configure: Drop texinfo requirement
  Remove Texinfo related line from git.orderfile
  scripts/texi2pod: Delete unused script
  docs/devel/qapi-code-gen.txt: Update to new rST backend conventions
  scripts/qapi: Remove texinfo generation support
  tests/qapi-schema: Add test of the rST QAPI doc-comment output
  meson.build: Make manuals depend on source to Sphinx extensions
  meson.build: Move SPHINX_ARGS to top level meson.build file
  tests/qapi-schema: Convert doc-good.json to rST-style strong/emphasis
  qga/qapi-schema.json: Add some headings
  qapi: Use rST markup for literal blocks
  docs/interop: Convert qemu-qmp-ref to rST
  docs/interop: Convert qemu-ga-ref to rST
  docs/sphinx: Add new qapi-doc Sphinx extension
  qapi/machine.json: Escape a literal '*' in doc comment
  scripts/qapi/parser.py: improve doc comment indent handling
  scripts/qapi: Move doc-comment whitespace stripping to doc.py
  tests/qapi/doc-good.json: Prepare for qapi-doc Sphinx extension
  qapi/block.json: Add newline after "Example:" for block-latency-histogram-set
  ...

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