[Mesa-dev] radv: initial vega support

[Dave Airlie]

This is an initial port of the vega code from radeonsi to radv.

It only support vertex/fragment shaders, tess/gs is going to
take a fair bit of work, but we don't have many tess/gs workloads
for radv yet, so it's not a major problem.

I've tested this on one very remote card, so can't try anything
more than the demos and some of CTS. Some CTS tests are failing
in unusual ways that may actually be kernel/fw bugs, and I'll
get to figuring those out later, also there might be still some
bugs in this, but it's a good start, I'd probably like to push
it all asap execpt for the enable if it makes things easier.

Dave.