Merge remote-tracking branch 'remotes/rth/tags/pull-tcg-20180615' into staging

TCG patch queue:

Workaround macos assembler lossage.
Eliminate tb_lock.
Fix TB code generation overflow.

# gpg: Signature made Fri 15 Jun 2018 20:40:56 BST
# gpg:                using RSA key 64DF38E8AF7E215F
# gpg: Good signature from "Richard Henderson <richard.henderson@linaro.org>"
# Primary key fingerprint: 7A48 1E78 868B 4DB6 A85A  05C0 64DF 38E8 AF7E 215F

* remotes/rth/tags/pull-tcg-20180615:
  tcg: Reduce max TB opcode count
  tcg: remove tb_lock
  translate-all: remove tb_lock mention from cpu_restore_state_from_tb
  cputlb: remove tb_lock from tlb_flush functions
  translate-all: protect TB jumps with a per-destination-TB lock
  translate-all: discard TB when tb_link_page returns an existing matching TB
  translate-all: introduce assert_no_pages_locked
  translate-all: add page_locked assertions
  translate-all: use per-page locking in !user-mode
  translate-all: move tb_invalidate_phys_page_range up in the file
  translate-all: work page-by-page in tb_invalidate_phys_range_1
  translate-all: remove hole in PageDesc
  translate-all: make l1_map lockless
  translate-all: iterate over TBs in a page with PAGE_FOR_EACH_TB
  tcg: move tb_ctx.tb_phys_invalidate_count to tcg_ctx
  tcg: track TBs with per-region BST's
  qht: return existing entry when qht_insert fails
  qht: require a default comparison function
  tcg/i386: Use byte form of xgetbv instruction

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