Merge remote-tracking branch 'remotes/stefanha/tags/tracing-pull-request' into staging

Merge remote-tracking branch 'remotes/stefanha/tags/tracing-pull-request' into staging

Pull request

 * Trace TCG atomic memory accesses
 * Document that trace event arguments cannot be floating point

# gpg: Signature made Wed 27 Jun 2018 13:57:40 BST
# gpg:                using RSA key 9CA4ABB381AB73C8
# gpg: Good signature from "Stefan Hajnoczi <stefanha@redhat.com>"
# gpg:                 aka "Stefan Hajnoczi <stefanha@gmail.com>"
# Primary key fingerprint: 8695 A8BF D3F9 7CDA AC35  775A 9CA4 ABB3 81AB 73C8

* remotes/stefanha/tags/tracing-pull-request:
  trace: forbid floating point types
  trace: enable tracing of TCG atomics
  trace: add trace_mem_build_info_no_se_be/le
  trace: expand mem_info:size_shift to 3 bits
  trace: simplify trace_mem functions
  trace: fix misreporting of TCG access sizes for user-space

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