Merge remote-tracking branch 'remotes/dgibson/tags/ppc-for-5.0-20200417' into staging

Merge remote-tracking branch 'remotes/dgibson/tags/ppc-for-5.0-20200417' into staging

ppc patch queue for 2020-04-17

Here are a few late bugfixes for qemu-5.0 in the ppc target code.
Unless some really nasty last minute bug shows up, I expect this to be
the last ppc pull request for qemu-5.0.

# gpg: Signature made Fri 17 Apr 2020 06:02:13 BST
# gpg:                using RSA key 75F46586AE61A66CC44E87DC6C38CACA20D9B392
# gpg: Good signature from "David Gibson <david@gibson.dropbear.id.au>" [full]
# gpg:                 aka "David Gibson (Red Hat) <dgibson@redhat.com>" [full]
# gpg:                 aka "David Gibson (ozlabs.org) <dgibson@ozlabs.org>" [full]
# gpg:                 aka "David Gibson (kernel.org) <dwg@kernel.org>" [unknown]
# Primary key fingerprint: 75F4 6586 AE61 A66C C44E  87DC 6C38 CACA 20D9 B392

* remotes/dgibson/tags/ppc-for-5.0-20200417:
  target/ppc: Fix mtmsr(d) L=1 variant that loses interrupts
  target/ppc: Fix wrong interpretation of the disposition flag.
  linux-user/ppc: Fix padding in mcontext_t for ppc64

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