Merge remote-tracking branch 'remotes/rth/tags/pull-mb-20200901' into staging

Merge remote-tracking branch 'remotes/rth/tags/pull-mb-20200901' into staging

Convert microblaze to generic translator loop
Convert microblaze to decodetree
Fix mb_cpu_transaction_failed
Other misc cleanups

# gpg: Signature made Tue 01 Sep 2020 16:17:19 BST
# gpg:                using RSA key 7A481E78868B4DB6A85A05C064DF38E8AF7E215F
# gpg:                issuer "richard.henderson@linaro.org"
# gpg: Good signature from "Richard Henderson <richard.henderson@linaro.org>" [full]
# Primary key fingerprint: 7A48 1E78 868B 4DB6 A85A  05C0 64DF 38E8 AF7E 215F

* remotes/rth/tags/pull-mb-20200901: (76 commits)
  target/microblaze: Reduce linux-user address space to 32-bit
  target/microblaze: Add flags markup to some helpers
  target/microblaze: Remove cpu_R[0]
  target/microblaze: Remove last of old decoder
  target/microblaze: Convert dec_stream to decodetree
  target/microblaze: Convert dec_msr to decodetree
  target/microblaze: Convert msrclr, msrset to decodetree
  target/microblaze: Tidy do_rti, do_rtb, do_rte
  target/microblaze: Convert dec_rts to decodetree
  target/microblaze: Convert dec_bcc to decodetree
  target/microblaze: Convert dec_br to decodetree
  target/microblaze: Reorganize branching
  target/microblaze: Convert mbar to decodetree
  target/microblaze: Convert brk and brki to decodetree
  target/microblaze: Tidy mb_cpu_dump_state
  target/microblaze: Replace delayed_branch with tb_flags_to_set
  target/microblaze: Replace clear_imm with tb_flags_to_set
  target/microblaze: Use cc->do_unaligned_access
  tcg: Add tcg_get_insn_start_param
  target/microblaze: Store "current" iflags in insn_start
  ...

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