Merge remote-tracking branch 'remotes/rth/tags/pull-tcg-20190709' into staging

Minor gvec fix for as-yet uncommitted altivec host.
Build fix for riscv host.

# gpg: Signature made Tue 09 Jul 2019 07:27:34 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-20190709:
  tcg: Fix expansion of INDEX_op_not_vec
  tcg/riscv: Fix RISC-VH host build failure

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