Merge remote-tracking branch 'remotes/armbru/tags/pull-qapi-2017-03-16' into staging

Merge remote-tracking branch 'remotes/armbru/tags/pull-qapi-2017-03-16' into staging

QAPI patches for 2017-03-16

# gpg: Signature made Thu 16 Mar 2017 06:18:38 GMT
# gpg:                using RSA key 0x3870B400EB918653
# gpg: Good signature from "Markus Armbruster <armbru@redhat.com>"
# gpg:                 aka "Markus Armbruster <armbru@pond.sub.org>"
# Primary key fingerprint: 354B C8B3 D7EB 2A6B 6867  4E5F 3870 B400 EB91 8653

* remotes/armbru/tags/pull-qapi-2017-03-16: (49 commits)
  qapi: Fix a misleading parser error message
  qapi: Make pylint a bit happier
  qapi: Drop unused .check_clash() parameter schema
  qapi: union_types is a list used like a dict, make it one
  qapi: struct_types is a list used like a dict, make it one
  qapi: enum_types is a list used like a dict, make it one
  qapi: Factor add_name() calls out of the meta conditional
  qapi: Simplify what gets stored in enum_types
  qapi: Drop unused variable events
  qapi: Eliminate check_docs() and drop QAPIDoc.expr
  qapi: Fix detection of bogus member documentation
  tests/qapi-schema: Improve coverage of bogus member docs
  tests/qapi-schema: Rename doc-bad-args to doc-bad-command-arg
  qapi: Move empty doc section checking to doc parser
  qapi: Improve error message on @NAME: in free-form doc
  qapi: Move detection of doc / expression name mismatch
  qapi: Fix detection of doc / expression mismatch
  tests/qapi-schema: Improve doc / expression mismatch coverage
  qapi2texi: Use category "Object" for all object types
  qapi2texi: Generate descriptions for simple union tags
  ...

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