Merge remote-tracking branch 'remotes/philmd-gitlab/tags/pflash-next-20190709' into staging

Restore 32-bit I/O accesses on AMD flashes
(precautionary revert).

# gpg: Signature made Tue 09 Jul 2019 16:18:10 BST
# gpg:                using RSA key E3E32C2CDEADC0DE
# gpg: Good signature from "Philippe Mathieu-Daudé (F4BUG) <f4bug@amsat.org>" [full]
# Primary key fingerprint: FAAB E75E 1291 7221 DCFD  6BB2 E3E3 2C2C DEAD C0DE

* remotes/philmd-gitlab/tags/pflash-next-20190709:
  Revert "hw/block/pflash_cfi02: Reduce I/O accesses to 16-bit"

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