Merge remote-tracking branch 'remotes/rth-gitlab/tags/pull-tcg-20210721' into staging

Atomic build fixes for clang-12
Breakpoint reorg

# gpg: Signature made Wed 21 Jul 2021 20:57:50 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-gitlab/tags/pull-tcg-20210721: (27 commits)
  accel/tcg: Record singlestep_enabled in tb->cflags
  accel/tcg: Hoist tb_cflags to a local in translator_loop
  accel/tcg: Remove TranslatorOps.breakpoint_check
  accel/tcg: Move breakpoint recognition outside translation
  accel/tcg: Merge tb_find into its only caller
  target/avr: Implement gdb_adjust_breakpoint
  hw/core: Introduce CPUClass.gdb_adjust_breakpoint
  target/i386: Implement debug_check_breakpoint
  target/arm: Implement debug_check_breakpoint
  hw/core: Introduce TCGCPUOps.debug_check_breakpoint
  accel/tcg: Use CF_NO_GOTO_{TB, PTR} in cpu_exec_step_atomic
  accel/tcg: Handle -singlestep in curr_cflags
  accel/tcg: Drop CF_NO_GOTO_PTR from -d nochain
  accel/tcg: Add CF_NO_GOTO_TB and CF_NO_GOTO_PTR
  target/alpha: Drop goto_tb path in gen_call_pal
  accel/tcg: Move curr_cflags into cpu-exec.c
  accel/tcg: Reduce CF_COUNT_MASK to match TCG_MAX_INSNS
  accel/tcg: Push trace info building into atomic_common.c.inc
  trace: Fold mem-internal.h into mem.h
  accel/tcg: Expand ATOMIC_MMU_LOOKUP_*
  ...

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