VertexProcessor multiSampling state was eliminated.

Change-Id: I0507c80faff9e00b36d26ea96e3bc3a8e837d574
Reviewed-on: https://swiftshader-review.googlesource.com/c/25569Tested-by: Nicolas Capens <nicolascapens@google.com>
Reviewed-by: Alexis Hétu <sugoi@google.com>