[VIRT-327 # Richard's upstream QEMU work ]

Some tcg-op-gvec work in support of MCA's target/ppc AltiVec work. But in the process filled in the blanks for target/arm to take advantage of the new entry points.

Rebased my August linux-user split work, reorg'ed for advice, and posted v5.

Reviewing Cota's dynamic sized tlb patch set. TODO: I want to update the aarch64 backend for this before finalizing a data structure layout.

[VIRT-339 # ARMv8.5-BTI, Branch Target Identification ]

Posted v1. We'll not talk about mailing lists any further. :-P

Merry Christmas, all!

r~