qemu-system-ppc SMP patches (WIP)

Not sure if anyone watches qemu-ppc mail list here, but we discovered
curious featurebug (?) that allow 4 * G4 cpus work in Linux and MacOS
X 10.4 (but not in 10.3 and earlier, nor in Leopard). NetBSD sadly
does not play along even with two processors, but may be someone
(Michael?) will have some hacky fun with it anyway?

Patches attached to forum post

https://forums.macrumors.com/threads/smp-for-qemu-syetem-ppc64-wip.2450008/page-2

But I can repost them here as zip archive (you need to patch openbios,
but I already included one pre-built with all 3 patches included)

Use-case I have in mind most is package building, even if nowadays
there is support for cross-compiling some packages by ./build.sh ?

Have some Power!