Merge remote-tracking branch 'remotes/rth/tags/pull-tcg-20200602' into staging

Vector rotate support
Signal handling support for NetBSD arm/aarch64

# gpg: Signature made Tue 02 Jun 2020 17:43:05 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-tcg-20200602:
  accel/tcg: Provide a NetBSD specific aarch64 cpu_signal_handler
  accel/tcg: Adjust cpu_signal_handler for NetBSD/arm
  tcg: Improve move ops in liveness_pass_2
  target/s390x: Use tcg_gen_gvec_rotl{i,s,v}
  target/ppc: Use tcg_gen_gvec_rotlv
  tcg/ppc: Implement INDEX_op_rot[lr]v_vec
  tcg/aarch64: Implement INDEX_op_rotl{i,v}_vec
  tcg/i386: Implement INDEX_op_rotl{i,s,v}_vec
  tcg: Implement gvec support for rotate by scalar
  tcg: Remove expansion to shift by vector from do_shifts
  tcg: Implement gvec support for rotate by vector
  tcg: Implement gvec support for rotate by immediate

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