Merge tpm 2018/02/21 v2

# gpg: Signature made Tue 27 Feb 2018 13:50:28 GMT
# gpg:                using RSA key 75AD65802A0B4211
# gpg: Good signature from "Stefan Berger <stefanb@linux.vnet.ibm.com>"
# gpg: WARNING: This key is not certified with a trusted signature!
# gpg:          There is no indication that the signature belongs to the owner.
# Primary key fingerprint: B818 B9CA DF90 89C2 D5CE  C66B 75AD 6580 2A0B 4211

* remotes/stefanberger/tags/pull-tpm-2018-02-21-2:
  tests: add test for TPM TIS device
  tests: Move common TPM test code into tpm-emu.c

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