Merge remote-tracking branch 'remotes/pmaydell/tags/pull-target-arm-20180302' into staging

target-arm queue:
 * implement FCMA and RDM v8.1 and v8.3 instructions
 * enable Cortex-M33 v8M core, and provide new mps2-an505 board model
   that uses it
 * decodetree: Propagate return value from translate subroutines
 * xlnx-zynqmp: Implement the RTC device

# gpg: Signature made Fri 02 Mar 2018 11:05:40 GMT
# gpg:                using RSA key 3C2525ED14360CDE
# gpg: Good signature from "Peter Maydell <peter.maydell@linaro.org>"
# gpg:                 aka "Peter Maydell <pmaydell@gmail.com>"
# gpg:                 aka "Peter Maydell <pmaydell@chiark.greenend.org.uk>"
# Primary key fingerprint: E1A5 C593 CD41 9DE2 8E83  15CF 3C25 25ED 1436 0CDE

* remotes/pmaydell/tags/pull-target-arm-20180302: (39 commits)
  target/arm: Enable ARM_FEATURE_V8_FCMA
  target/arm: Decode t32 simd 3reg and 2reg_scalar extension
  target/arm: Decode aa32 armv8.3 2-reg-index
  target/arm: Decode aa32 armv8.3 3-same
  target/arm: Decode aa64 armv8.3 fcmla
  target/arm: Decode aa64 armv8.3 fcadd
  target/arm: Add ARM_FEATURE_V8_FCMA
  target/arm: Enable ARM_FEATURE_V8_RDM
  target/arm: Decode aa32 armv8.1 two reg and a scalar
  target/arm: Decode aa32 armv8.1 three same
  target/arm: Decode aa64 armv8.1 scalar/vector x indexed element
  target/arm: Decode aa64 armv8.1 three same extra
  target/arm: Decode aa64 armv8.1 scalar three same extra
  target/arm: Refactor disas_simd_indexed size checks
  target/arm: Refactor disas_simd_indexed decode
  target/arm: Add ARM_FEATURE_V8_RDM
  mps2-an505: New board model: MPS2 with AN505 Cortex-M33 FPGA image
  hw/arm/iotkit: Model Arm IOT Kit
  hw/misc/iotkit-secctl: Add remaining simple registers
  hw/misc/iotkit-secctl: Add handling for PPCs
  ...

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