fixup! tcg-ppc64: Setup TCG_REG_TB
tcg-ppc64: Tidy tcg_target_qemu_prologue

Use the helper macros like TAI.  Fix formatting.

Signed-off-by: Richard Henderson <rth@twiddle.net>
tcg-ppc64: Streamline tcg_out_tlb_read

Less conditional compilation.  Merge an add insn with the indexed
memory load insn.  Load the tlb addend earlier.  Avoid the address
update memory form.

Signed-off-by: Richard Henderson <rth@twiddle.net>
tcg-ppc64: Implement CONFIG_QEMU_LDST_OPTIMIZATION

Signed-off-by: Richard Henderson <rth@twiddle.net>