To avoid to many #ifdef in target code, provide a tlb_vaddr_to_host for
both user and softmmu modes. In the first case the function always
succeed and just call the g2h function.
Backports commit 2e83c496261c799b0fe6b8e18ac80cdc0a5c97ce from qemu
At 8k per TLB (for 64-bit host or target), 8 or more modes
make the TLBs bigger than 64k, and some RISC TCG backends do
not like that. On the affected hosts, cut the TLB size in
half---there is still a measurable speedup on PPC with the
next patch.
Backports commit 1de29aef17a7d70dbc04a7fe51e18942e3ebe313 from qemu
Support guest CPUs which need 7 MMU index values.
Add a comment about what would be required to raise the limit
further (trivial for 8, TCG backend rework for 9 or more).
Backports commit 8f3ae2ae2d02727f6d56610c09d7535e43650dd4 from qemu
