Merge remote-tracking branch 'remotes/stsquad/tags/pull-testing-next-260919-1' into...

Merge remote-tracking branch 'remotes/stsquad/tags/pull-testing-next-260919-1' into staging

Testing updates plus alpha FP fixes:

  - fix alpha handling of FtoI overflow
  - various docker cleanups
  - fix docker.py cleanup race
  - fix podman invocation
  - tests/tcg: add float and record/replay tests
  - remove unused docker images
  - expand documentation for check-tcg

# gpg: Signature made Thu 26 Sep 2019 19:33:38 BST
# gpg:                using RSA key 6685AE99E75167BCAFC8DF35FBD0DB095A9E2A44
# gpg: Good signature from "Alex Bennée (Master Work Key) <alex.bennee@linaro.org>" [full]
# Primary key fingerprint: 6685 AE99 E751 67BC AFC8  DF35 FBD0 DB09 5A9E 2A44

* remotes/stsquad/tags/pull-testing-next-260919-1: (28 commits)
  tests/docker: remove debian-powerpc-user-cross
  docker: move tests from python2 to python3
  docker: remove unused debian-sid
  docker: remove unused debian-ports
  docker: remove 'deprecated' image definitions
  docker: remove unused debian8 partial image
  docker: remove debian8-mxe definitions
  target/i386: Fix broken build with WHPX enabled
  docs/devel: add "check-tcg" to testing.rst
  configure: preserve PKG_CONFIG for subdir builds
  tests/tcg: add simple record/replay smoke test for aarch64
  tests/tcg: add generic version of float_convs
  tests/tcg: add float_madds test to multiarch
  tests/tcg: re-enable linux-test for ppc64abi32
  tests/tcg: clean-up some comments after the de-tangling
  podman: fix command invocation
  tests/docker: reduce scary warnings by cleaning up clean up
  tests/docker: remove python2.7 from debian9-mxe
  tests/docker: fix DOCKER_PARTIAL_IMAGES
  tests/docker: add sanitizers back to clang build
  ...

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