d3dretrace: Use D3DCREATE_SOFTWARE_VERTEXPROCESSING for --driver=sw.
d3dretrace: Use D3DCREATE_SOFTWARE_VERTEXPROCESSING for --driver=sw.

Ideally we'd use the WARP, but I failed to find a way to use WARP on
demand for D3D9.  (The only solution is to disable the  GPU driver,
or to use a Windows 8.x/10 VM without any virtual GPU, but neither is
practical.)

apitrace/apitrace,apitrace/apitrace,apitrace/apitrace,apitrace/apitrace